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Unit 2:

Matter and Change (Chapter 2)

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Elements, Compounds, and Mixtures

There are three types of matter that are really great And during this lesson you will add them to your slate.

If you can master their properties and traits You will really impress your homecoming date!

Elements are building blocks

From which all things are made. They are all pure and can be found on a special table

And each of them has their own unique label. They’re made up of only one type of atom

And to separate them, it’s tough, as you can imagine. A nuclear reaction can accomplish this feat

You might never see this, what a bummer, it’s really neat.

Compounds are made from two or more different atoms put together. They can be separated chemically, not by the weather.

A chemical formula identifies this type of matter And the elements combine in a definite proportion, not like a cake batter.

Compounds form from elements, And, ‘though it may seem strange,

When they form a compound, Their properties all change.

As chemicals combine, Their particles rearrange,

To form some different substance, With an identity that completely changed.

Mixtures are different and don’t use chemical action They combine physically and don’t require a reaction.

They are homogeneous or heterogeneous in nature And are referred to respectfully as a solution and mixture.

With solutions & mixtures, it’s so different,

And there’s one thing you can bet— Put salt and water together, It will still be salty and wet.

‘Though you might fear changes, There’s no reason to fret.

Without chemical combination There’s nothing new to get.

Chemicals are everywhere-

One of life’s permanent fixtures. Yes, chemicals really matter-

Those elements, comp0unds, and mixtures!

Elements are simple things that can’t be broken down.

When put together chemically, They always form compounds. But thinking of the usual way

That chemicals are found, It’s jumbled up in mixtures that most chemicals abound.

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Elements, Compounds, and Mixtures Use what you’ve learned from the poem to answer the following questions. 1. According to the poem, what are the three forms in which matter is found? _________________ 2. Which of the main types of matter can be separated physically? ____________________________ 3. Which of the main types of matter must be separated chemically? __________________________ 4. A mixture with a homogeneous composition is called a _______________________________. 5. T/F: When a compound is formed, a substance with a new identity is formed. _________ 6. T/F: When elements combine to form a compound, they do so in an indefinite proportion. ____ 7. Why is it that when you mix salt and water together, “It will still be salty and wet?” ___________ ____________________________________________________________________________________ 8. Hydrogen is an explosive gas, and oxygen supports combustion. How is it possible, then, for water, which is composed of hydrogen and oxygen, to put out fires? Quote the lines in the poem that explain this. _______________________________________________________________ ____________________________________________________________________________________ 9. Indicate whether each of the following describes an element, compound, or mixture:

a. physical combination of more than one substance ___________________ b. simple substance that can’t be broken down by ordinary means ___________________ c. chemical combination of two or more kinds of atoms ___________________ d. gold ___________________ e. air ___________________ f. juice ___________________ g. sugar ___________________ h. oxygen ___________________ i. table salt ___________________

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Matter

Homogeneous Heterogeneous

Solution Pure Substance

Element Compound

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Element Compound Mixture Pure Substance?

What is the composition of the substance & how are the atoms combined?

How can the substance be separated?

Describe the proportion of the components in each substance.

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Elements, Compounds, Mixtures

1. Describe the difference between a heterogeneous mixture and a homogeneous mixture. Give an

example of each.

2. Identify each of the following samples of matter as homogeneous (HOM) or heterogeneous (HET).

a. soil __________ e. iron __________

b. table sugar __________ f. river water __________

c. nitrogen __________ g. cough syrup __________

d. olive oil __________ h. gasoline __________

3. Classify each of the following as homogeneous (HOM) or heterogeneous (HET) mixtures.

a. flat soda __________

b. chocolate chip ice cream __________

c. sand in water __________

d. brass __________

e. salt water __________

4. How would you separate the following mixtures?

a. Iron filings from aluminum filings

______________________________________________________________________________

b. sawdust from sand

______________________________________________________________________________

c. salt water

______________________________________________________________________________

5. Describe the difference between a pure substance and a solution. Give examples of each.

6. Classify each of the samples of matter from Problem 2 as one of the following: element (E), compound (C), heterogeneous mixture (HET), solution (SOL’N).

a. soil __________ e. iron __________

b. table sugar __________ f. river water __________

c. nitrogen __________ g. cough syrup __________

d. olive oil __________ h. gasoline __________

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LAW OF DEFINITE COMPOSITION

A __________________ compound contains the same _________________ in _________________

the same __________________ by ______________, regardless of the size of the __________________

or the source of the ________________________.

Vitamin C (____________________________) made in the lab is chemically identical to

naturally occurring vitamin C

If the ________________________ of the elements is ______________________ the compound

becomes a new ______________________________

Example: H2O is water with a ratio of _____H / ____O

If you change the _______________ to 2H/2O, the compound is no longer H2O.

It is now H2O2, ___________________________________.

PROPERTIES OF MATTER 1. Physical Properties

Can be _______________ or ________________________ without altering the

____________________ of the _______________________.

Extensive Physical Properties Depends on the __________________ of _____________________ present.

Ex: ___________________________________________________ Intensive Physical Properties

Does _____________ depend on the _____________________ of matter present.

Ex: ___________________________________________________ 2. Chemical Properties

Describe ____________________ changes

How a ______________________ reacts with other ___________________________

Ex: ___________________________________________________

Usually Signify a _____________________ ___________________!

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CHANGES OF MATTER Physical Change

Change that __________________ a substance ____________________ changing its

_________________________

Examples: Change in ______________________________

Change in ______________________________

Change in ______________________________

Change in ______________________________

Chemical Change When a substance is _________________________ into a new substance with a

____________________________ set of ________________________

Indications of a chemical change has occurred: Evolution of _________________ and _______________________

Production of ___________________________

Formation of __________________________________

Production of ____________________________

Drastic _____________________________

A chemical change is also called a ____________ ______________

Reactants – the substance(s) that _____________________ a chemical reaction.

The ______________________ that _________________.

Products – the new substance(s) _____________________ by a chemical reaction. Example: ____________________________________________________

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ENERGY The ________________________________________________________________.

The Law of Conservation of Energy – ________________________________________________

_______________________________________________________________________________________

_______________________________________________________________________________________

All ENERGY (E) is classified as: _________________ or _________________

1. Kinetic E the E of an object in ____________________

2. Potential E

the E of an object has due to its ________________________

Chemical and Physical changes are accompanied by _____________ changes

Reactions involving E changes are either:

1. ______________________________

2. ______________________________

Everything strives to be at the _________________ possible E

Exothermic

The _________________ of heat

E flows out of the _____________________ into the _________________________

E _____________ by __________________ = E lost by _________________________

Reaction vessel feels ____________________!!

Endothemic

The _________________ of heat

E flows into the ____________________ from _______________________

E ______________ by _______________ = E lost by _____________________

Reaction vessel feels ____________________!!

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Physical vs. Chemical?

1. Classify each of the following as a chemical (C) or physical (P) property.

a. colorless __________

b. produces a gas when sodium metal is dropped onto it __________

c. changes from a liquid to a solid at 00C __________

d. can be decomposed by electricity into the elements hydrogen and oxygen __________

e. condenses at 1000C __________

f. is a liquid at room temperature __________

g. produces acetylene gas when dropped onto calcium carbide __________

2. Classify each of the following properties of the element silicon as chemical (C) or physical (P).

a. blue-gray color __________ e. reacts vigorously with fluorine __________

b. brittle __________ f. shiny __________

c. insoluble in water __________ g. unreactive in water __________

d. melts at 1410C __________

3. List the five indications of a chemical change.

a. _________________________________________________________________

b. _________________________________________________________________

c. _________________________________________________________________

d. _________________________________________________________________

e. _________________________________________________________________

4. Classify each of the following as a chemical (C) or physical (P) change.

a. bending a piece of wire __________ f. stretching a rubber band __________

b. burning coal __________ g. cutting grass __________

c. cooking a steak __________ h. a snowflake melts __________

d. dissolving sugar in water __________ i. water boils __________

e. milk sours __________ j. a firefly emits light __________

5. What evidence do you observe that convinces you that each of the following is a chemical change?

a. food spoils ___________________________________________

b. a foaming antacid tablet fizzes in water ___________________________________________

c. a ring of scum forms around your bathtub ___________________________________________

d. iron rusts ___________________________________________

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Unit 2 ~ Problem Set #1 Pg. 58-60; #36, 42, 46, 49, 54, 56, 57, 60, 62, 63, 68, 72 36. List three physical properties of copper.

________________________________________________________________________________ 42. Use table 2.1 (pg. 40) to identify four substances that undergo a physical change if the

temperature is reduced from 500C to -500C. What is the physical change that takes place in each case?

_________________________________________________________________________________ 46. Classify each of the following as homogeneous or heterogeneous mixtures.

a. chocolate chip ice cream __________________ c. cake batter _________________ b. green ink __________________ d. cooking oil _________________

49. Describe the relationship between the three items in each of the following groups. Identify

each item as an element, compound or mixture.

a. hydrogen, oxygen, water________________________________________________________ _________________________________________________________________________________

b. nitrogen, oxygen, air____________________________________________________________

_________________________________________________________________________________

c. sodium, chlorine, table salt______________________________________________________ _________________________________________________________________________________ d. carbon, water, table sugar_______________________________________________________

_________________________________________________________________________________

54. Classify each of the following as a physical or chemical change. For any chemical change, list at least one clue to support your answer. a. a copper wire is bent. ___________________________________________________________ b. charcoal burns in a grill __________________________________________________________ c. bread dough rises when yeast is added ____________________________________________ d. sugar dissolves in water _________________________________________________________

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56. When ammonia nitrate (NH4NO3) explodes, the products are nitrogen, oxygen, and water. When 40 grams of ammonium nitrate explode, 14 grams of nitrogen and 8 grams of oxygen form. How many grams of water form?

_________________________________________________________________________________

57. Explain why mass cannot be used as a property to identify a sample of matter.

_________________________________________________________________________________

Use the following chart to answer #60 – 63.

Substance Color Melting Point (oC)

Boiling Point (0C)

Bromine red-brown -7 59

Chlorine green-yellow -101 -34

Ethanol colorless -117 78

Mercury silvery-white -39 357

Neon colorless -249 -246

Sulfur yellow 115 445

Water colorless 0 100

60. Which colorless substance is a liquid at -300C? _____________________ 62. Which substance is a solid at 70C? _____________________ 63. As the temperature rises, which solid melts before mercury boils? ____________ 68. How are the items in each of the following pairs similar/different?

a. copper and silver _______________________________________________________________

___________________________________________________________________________

b. distilled water and saltwater_____________________________________________________ ___________________________________________________________________________ c. table sugar and table salt________________________________________________________ _________________________________________________________________________________

72. The wax appears to disappear as a candle burns. How can the law of conservation of mass

apply to this reaction?

_________________________________________________________________________________ _________________________________________________________________________________

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Finding Out About Matter A. Classifying mixtures as homogeneous or heterogeneous

A homogeneous mixture is a mixture whose composition is constant throughout, having identical

properties in every part. It is usually called by the more familiar term, solution. A heterogeneous mixture

has different properties throughout the material. The composition varies depending on where the

sample was taken.

Classify each of the following as heterogeneous (HET) or homogeneous (HOM).

__________ sweetened hot tea __________ bag of leaves __________ cake batter w/ m&ms

__________ brass __________ dental filling __________ shampoo

__________ root beer float __________ motor oil __________ Hershey’s syrup

__________ hand lotion __________ brownies with nuts __________ granite

B. Classifying materials as elements, compounds, or mixtures

Substances that contain only one kind of atom are called elements. Elements are the fundamental units

which cannot be broken down into smaller units by chemical means. Substances that are chemical

combinations of two or more elements are called compounds. A compound can be broken down into

elements or other compounds by chemical means only. Combinations of two or more substances that

retain their separate identities are mixtures. Unlike the definite composition of a compound, the

composition of a mixture may vary. Mixtures can be separated by physical means, such as distillation or

filtration.

Classify the following as an element (E), compound (C), heterogeneous mixture (HET) or solution (SOL'N).

__________ sodium chloride __________ iron rod __________ stainless steel

__________ hamburger relish __________ concrete __________ old paint in a can

__________ Diet Coke __________ Exxon gasoline __________ dirt

__________ skim milk __________ copper wire __________ 14 karat gold

__________ mayonnaise __________ antifreeze __________ distilled water

__________ calcium chloride __________ rust __________ carbon monoxide

__________ OJ with pulp __________ Raisin Bran __________ aluminum foil

__________ pizza __________ a new penny __________ copper II sulfate

__________ cream of tomato soup __________ fresh air __________ potting soil

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C. Classifying chemical and physical properties

A chemical property is one which describes the chemical nature of a substance — how it reacts with

other substances. In order to observe a chemical property, the composition of the original material must

be changed. For example, a chemical property of sugar is that it burns (reacts with oxygen) to form

carbon and other products. A black, burned marshmallow is chemically different from a white, fluffy

one. A physical property is one which describes the appearance, the phase, or any behavior that does

not change its chemical makeup. The composition of the material remains the same. For example,

when a rubber band is stretched, it is still the same material.

Classify each of the following as a physical or chemical property.

__________ Peanut brittle breaks very easily.

__________ Ethyl alcohol freezes at -117 °C.

__________ Digesting a hot dog produces 175 kcal of energy.

__________ Ammonia’s strong smell makes it useful to revive people.

__________ Although oxygen gas appears colorless, liquid oxygen has a pale blue color.

__________ Water boils at 50 °C on Mt. Everest.

__________ Copper sulfate, a crystalline blue solid, dissolves in water to create a blue solution.

D. Classifying chemical and physical changes

A change that produces a new kind of matter with different properties is called a chemical change.

When a chemical change has occurred, a chemical reaction has taken place. When a fluffy white

marshmallow burns, it has undergone a chemical change which created new substances with different

properties from the marshmallow. A change that does not affect the chemical composition of the

material is called a physical change. When a marshmallow is smashed, its size and density have

changed (and it may not seem to taste as good), but it still has the same chemical composition as the

fluffy one.

Classify each of the following as a physical or chemical change.

__________ Your great-grandmother’s silver platter tarnishes.

__________ Butter melts into the nooks and crannies of a Thomas English muffin.

__________ Wood burns in a fireplace to produce heat and a cozy, romantic atmosphere.

__________ Grape juice ferments to form wine.

__________ Silver metal is hammered into thin sheets to make jewelry.

__________ Sweat cools the body as it evaporates from the skin.

__________ Milk of magnesia neutralizes stomach acid.

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Name ____________________________________________________ Period ___________________

MATTER - Vocabulary Review Match the correct vocabulary term to each numbered statement. Write the letter of the correct term on the line. Each answer can only be used once. a. extensive property f. solid k. mixture

b. physical change g. solution l. intensive property

c. heterogeneous h. gas m. liquid

d. endothermic i. compound n. exothermic

e. element j. chemical change o. law of definite composition ___________ 1. Matter that has a definite shape and volume.

___________ 2. Two or more elements chemically combined.

___________ 3. Matter that is not uniform in composition and contains more than one set of

properties.

___________ 4. A chemical compound contains the same elements in exactly the same

proportion by mass, regardless of the size of the sample or source of the

compound.

___________ 5. Matter that has a definite volume but takes the shape of the container.

___________ 6. A process that releases heat to its surroundings.

___________ 7. A property that depends on the type of matter in a sample, not the amount.

___________ 8. A homogeneous mixture of two or more substances in a single phase.

___________ 9. A change that alters a substance without changing its composition.

__________10. A process that absorbs heat from its surroundings.

__________11. Matter that has neither a definite shape nor definite volume.

__________12. Two or more substances physically combined.

__________13. When a substance is converted into a new substance with a different set of

properties.

__________14. A property that depends on the amount of matter in a sample.

__________15. The simplest form of matter that has a unique set of properties and cannot be

broken down into simpler substances by ordinary chemical means.

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Element Crossword

How many do you already know?

ACROSS DOWN 3. Na 1. Si 5. C 2. Ar 7. N 3. S 8. B 4. H 9. Al 6. P 14. Be 10. Li 15. He 11. Mg 16. F 12. O 17. Ne 13. Cl

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The Periodic Table Video

Pre-Quiz

TRUE/FALSE: Before watching the movie, test your knowledge by answering the following questions.

______ 1. One of the first war gases was bromine.

______ 2. The Hindenburg met a disastrous end because it was filled with the buoyant gas nitrogen.

______ 3. The element sulfur is found near volcanic activity.

______ 4. Metals and nonmetals can be distinguished by their solubility in water.

______ 5. Mendeleev arranged the elements on his Periodic Table by atomic number.

______ 6. Groups on the periodic table run vertically.

______ 7. In the noble gas family, density decreases as you proceed from the top to the bottom.

______ 8. Sodium and lithium react with oxygen by turning darker. Both metals react with water, but

sodium undergoes a more vigorous reaction than lithium.

______ 9. Hydrogen is the tyrannosaurus rex of all the elements.

______ 10. When a diamond is burned, water is the only product formed.

______ 11. When silicon is burned, the common name for the product is silicone, the substance used in fake

boobs.

______ 12. Along with copper, gold and silver are unreactive in water.

______ 13. Because of some leftover elements in odd groups or graveyards, the periodic table was

rearranged according to the “rulebook” so that there were metals, metalloids, and gases.

______ 14. According to American English, the host mispronounces the elements titanium and xenon.

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The Periodic Table

While watching the movie, increase your knowledge and answer the following questions.

1. One of the first war gases was

a) oxygen. b) chlorine. c) bromine. d) phosgene.

2. The Hindenburg met a disastrous end because it was filled with the buoyant gas

a) hydrogen. b) nitrogen. c) oxygen. d) helium.

3. What element is found near volcanic activity?

a) bromine b) carbon c) hydrogen d) sulfur

4. Metals and nonmetals can be distinguished by their

a) hardness. b) conductivity. c) solubility in water. d) melting points.

5. Mendeleev arranged the elements on his Periodic Table by

a) atomic number. b) atomic weight. c) isotope number. d) electron weight.

6. Groups on the periodic table run

a) horizontally. b) diagonally. c) vertically. d) in a stepwise pattern.

7. In the noble gas family, density increases as you proceed from

a) left to right. b) right to left. c) top to bottom. d) bottom to top.

8. Sodium and lithium react with oxygen by turning darker. Both metals react with water, but sodium

undergoes a more vigorous reaction than lithium.

a) true b) false

9. _____________ is the tyrannosaurus rex of all the elements.

a) Hydrogen b) Fluorine c) Francium d) Radon

10 When a diamond is burned, _____________ is the only product formed.

a) carbon b) sulfuric acid c) water d) carbon dioxide

11 When silicon is burned, the common name for the product is

a) sand. b) silicon dioxide. c) silicone. d) glass.

12. Along with copper, _________ are unreactive in water.

a) nickel & cobalt b) lead & tin c) zinc & mercury d) gold & silver

13. Because of some leftover elements in odd groups or graveyards, the periodic table was rearranged

according to the “rulebook” so that there were metals, metalloids, and

a) isotopes. b) gases. c) nonmetals. d) noble gases.

14. According to American English, the host mispronounces the elements __________ and xenon.

a) silicon b) aluminum c) titanium d) chlorine

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Introduction to the Periodic Table DIRECTIONS: After reading pages 808, 158-166, and 118, use a PENCIL answer the following questions.

1. The Periodic Table is an organization of all the known ____________________.

2. The first 92 elements, from ____________________ to ____________________, are found in

nature in either free or combined form.

3. The elements beyond uranium are called _________________________ elements. None of these

occurs in nature but are synthesized in nuclear reactors and all of them are _________________.

4. Chemists divide the elements into three classes. ____________________ ____________________

and __________________.

5. The largest class of elements contains metals. Where are the metals found on the periodic

table? _____________________________________________________________________________

6. All metals exist as solids at room temperature, except for ____________________, which exists as

a liquid.

7. Most metals have the following characteristics. Place the correct vocabulary word that

describes each characteristic.

1. ability to reflect light _________________________

2. conductors of heat and electricity (poor/good) _________________________

3. ability to be drawn into thin wires _________________________

4. ability to be hammered into thin sheets _________________________

8. What two qualities does copper have that makes it suitable for use in electrical cables?

___________________________________________________________________________________

9. What three properties does silver display that makes it popular in jewelry?

___________________________________________________________________________________

10. Where are the nonmetals located on the periodic table? ________________________________

11. Most nonmetals are __________________ at room temperature, a few are solids, and only one,

____________________ is a liquid. Unlike metals, nonmetals do not have a distinguishing set of

properties. In general, one property they all share is that they are _____________ conductors of

heat and electricity. Solid nonmetals (C, P, S, and I) tend to be __________________.

12. A special class of nonmetals is the diatomic elements. These seven elements are never found

alone in nature as atoms; they always occur in pairs. Therefore, the prefix “di-” means two in

chemistry. Name the seven diatomic elements and list their symbols ________________________

_____________________________________________________________________________________

13. Where are the metalloids located on the periodic table? __________________________________

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14. In terms of their properties, what is special about metalloids? ______________________________

____________________________________________________________________________________

15. List the names and symbols of the seven metalloids:

1. _________________________ 4. _________________________ 7. __________________

2. _________________________ 5. _________________________

3. _________________________ 6. _________________________

16. Vertical columns on the PT are called __________________ or __________________.

17. T/F: The elements within a group have similar chemical and physical properties. ___________

18. The elements in column IA (1), are called the __________________ __________________. They

form very strong bases when mixed with water.

19. Hydrogen is placed in column IA because it acts like a metal when reacting with other nonmetals.

However, hydrogen is NOT a metal; it is a __________________.

20. Group IIA (2), which is composed of all metals, is called the __________________

__________________ family. These metals also form __________________when mixed with water

but are not as reactive as group IA elements.

21. If one examines groups IIIA (3) to VIA (16), one can see that all the elements in those columns

do/do not belong to the same class of elements. Therefore, chemists do not give these families

a special name.

22. Group VIIA (17) are called the __________________, Greek for __________________ producers.

23. Column VIIIA (18) contains the __________________ __________________, sometimes called the

__________________ gases because they rarely take part in a chemical reaction.

24. Groups IA (1) through VIIIA (18) can be classified into one category. Elements in these groups

are often referred to as ______________________ ____________________ because all classes of

elements are represented within these groups.

25. How many rows are on the PT? __________

26. Rows are commonly referred to as __________________.

27. T/F: Within a period, the properties of the elements vary as you move across it from element to

element. _______________

28. The center section of the PT contains the B groups. What are these elements called?

_______________________ ______________________

29. Lastly, the __________________ transition metals appear below the main body of the table. This

section consists of two rows called the __________________ series and __________________

series. As a whole, these two rows of metals are sometimes referred to by their old-fashioned

name, the __________________ - __________________ elements.

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The Periodic Table Review SECTION 6.1 ORGANIZING THE ELEMENTS (pages 155-160) Searching For An Organizing Principle (page 155)

1. What caused the rate of discovery to increase after 1700? ______________________________________________________________________________

2. What did chemists use to sort elements into groups?

______________________________________________________________________________

Mendeleev’s Periodic Table

3. Who was Dmitri Mendeleev? ______________________________________________________

______________________________________________________________________________

4. What property did Mendeleev use to organize the elements into a periodic table?

______________________________________________________________________________

5. Is the following sentence true or false? Mendeleev used his periodic table to predict the properties of undiscovered elements. ____________________

The Periodic Law (page 157)

6. How are the elements arranged in the modern periodic table?

______________________________________________________________________________

7. True or false? The periodic law states that when elements are arranged in order of increasing atomic number, there is a periodic repetition of physical and chemical properties. _____________

Metals, Nonmetals, and Metalloids (pages 158-160)

8. Explain the color coding of the squares in the periodic table in figure 6.5.

______________________________________________________________________________ ______________________________________________________________________________

9. Which property below is NOT a general property metals. a. ductile c. malleable b. poor conductor of heat d. high luster

10. Is the following statement true or false? The variation in properties among metals is greater than

the variation in properties among nonmetals. ___________________ 11. Under some conditions, a metalloid may behave like a _________________________.

Under other conditions, a metalloid may behave like a _________________________.

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SECTION 6.2 CLASSIFYING THE ELEMENTS (pages 161-167) Squares In The Periodic Table (page 161-163)

12. Label the sample square from the periodic table below. Use the labels element name, element symbol, atomic number and average atomic mass.

Electron Configurations in Group (page 164-165)

13. Classify each of the following as a/an alkali metal, alkaline earth metal, halogen, or noble gas.

a. sodium ___________________ e. xenon _____________________

b. chlorine ___________________ f. potassium _____________________

c. calcium ___________________ g. magnesium _____________________

d. fluorine ___________________ Match the category of elements with an element from that category.

14. ____________ noble gas a. gallium 15. ____________ representative elements b. nobelium

16. ____________ transition metals c. argon

17. ____________ inner transition metals d. vanadium

Matching – match each term with the correct description.

18. ____________ metals a. a vertical column of elements in the periodic table

19. ____________ periods b. good conductors of heat and electric current

20. ____________ group c. poor conductors of heat and electric current

21. ____________ nonmetals d. have properties that are similar to those of metals and nonmetals

22. ____________ metalloids e. the horizontal rows of the periodic table

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Periodic Table of the Elements

H 1

1.01

Li 3

6.94

Na 11

23.0

K 19

39.10

Rb 37

85.47

Cs 55

132.90

Fr 87

(223)

Ca 20

40.08

Sr 38

87.62

Ba 56

137.30

Ra 88

(226)

Mg 12

24.31

Be 4

9.01

Sc 21

44.96

Y 39

88.91

Lu 71

175.00

Lr 103

(257)

Ti 22

47.88

Zr 40

91.22

Hf 72

178.50

Rf 104

(257)

V 23

50.94

Nb 41

92.91

Ta 73

180.90

Db 105

(260)

Cr 24

52.006

Mo 42

95.94

W 74

183.90

Sg 106

(263)

Mn 25

54.94

Tc 43

(98 )

Re 75

186.20

Bh 107

(262)

Fe 26

55.85

Ru 44

101.10

Os 76

190.20

Hs 108

(265)

Co 27

58.93

Rh 45

102.90

Ir 77

192.20

Mt 109

(266)

48

112.40

49

114.80

52

127.60

53

126.90

Ni 28

58.69

Cu 29

63.55

Zn 30

65.39

Ga 31

69.72

Ge 32

72.59

As 33

74.92

Se 34

78.96

Br 35

79.90

Kr 36

83.80

Pd 46

106.40

Ag 47

107.90

Cd In Sn 50

118.70

Sb 51

121.80

Te I Xe 54

131.30

At

Uun 110

Uuu 111

Uub Uuq 114

Pt 78

195.10

Au 79

197.00

Hg 80

200.60

Tl 81

204.40

Pb 82

207.20

Bi 83

209.00

Po 84

(210)

85

(210)

Rn 86

(222)

116

Uuh 112

(227) 232.00 (231) 238 (237) (242) (243) (247) (249) (254) (253) (247) (256) (254)

89 90 93

La 57

138.90

Ce 58

140.10

Pr 59

140.90

Nd 60

144.20

Pm

61

(147)

Sm 62

150.40

Eu 63

152.00

64

157.30 Tb

65

158.90

95

Ac Th Pa U Np Pu Am

Dy Ho Er Tm Yb

Cf Es Fm Md No Cm Bk

167.30 168.90 173.00

66 67 68 69 70

98 99 100 101 102 91 92 94 96 97

Gd

3 IIIB 3B

4 IVB 4B

5 V5 5B

6 VIB 6B

7 VIIB 7B

8 9 VIIIB

8

10

11 IB 1B

12 IIB 2B

Al 13

26.98

Si 14

28.09

P 15

30.97

S 16

32.06

Cl 17

35.45

Ar 18

39.95

B 5

10.81

C 6

12.01

N 7

14.01

O 8

16.00

F 9

19.00

Ne 10

20.18

2

He 4.00

164.90 162.50

1 IA

1A

2 IIA 2A

13 IIIA 3A

14 VIA 4A

15 VA 5A

16 VIA 6A

17 VIIA 7A

18 VIIIA 8A

26

Activity Series of Halogens

fluorine chlorine bromine iodine

Activity Series of Metals

lithium rubidium potassium

barium strontium calcium sodium

magnesium

aluminum manganese

zinc chromium

iron cadmium

cobalt nickel

tin lead

hydrogen copper

mercury silver gold

Academic Chemistry “Cheat Sheet”

Types of Chemical Reactions

A. Composition A + B AB 1. two elements a binary compound 2. metallic oxide + water a base (metallic hydroxide) 3. nonmetallic oxide + water an acid

B. Decomposition AB A + B

1. binary compound two elements 2. base metallic oxide + water 3. acid nonmetallic oxide + water 4. metallic carbonate metallic oxide + carbon dioxide 5. metallic chlorate metallic chloride + oxygen gas 6. hydrated salt salt + water

C. Single Replacement A + BX B + AX ; X + AY Y + AX

1. active metal (or H2) + ionic cmpd new metal (or H2) + ionic cmpd 2. active halogen + ionic halide halogen + ionic compound

D. Double Replacement AX + BY AY + BX

1. two soluble ionic compounds two new compounds, one of which must be an insoluble ionic compound or a molecular compound

Steps for Solving a Reaction Stoichiometry Problem

Common Polyatomic Ions

Name Formula

ammonium

NH4+1

acetate C2H3O2-1

bicarbonate HCO3-1

chlorate ClO3-1

cyanide CN-1 cyanate CNO-1

hydroxide OH-1 nitrate NO3

-1 permanganate KMnO4

-1

thiocyanate SCN- carbonate CO3

-2 chromate CrO4

-2 dichromate Cr2O7

-2 peroxide O2

-2 sulfate SO4

-2 phosphate PO4

-3

GRAMS of reactant

or product

MOLES of reactant

or product

MOLES of new reactant

or new product

GRAMS of new reactant

or new product

use molar mass

of R or P

use mole ratio of R or P

use molar mass

of R or P

Solubility Chart

positive ion negative ion

Na+, K+, NH4

+

NO3-, C2H3O2

-, ClO3-

soluble

silver, mercury, lead

CO3

-2, PO4-3, S-2, OH-

insoluble

Cl-1, Br-1, I-1

soluble

Ba+2, Ca+2, Sr+2

insoluble

SO4

-2

soluble

27

On the blank periodic table, clearly locate the following. Use a color code or some other means for easy identification.

A. representative elements B. transition elements C. inner transition elements

D. metals E. nonmetals F. metalloids

G. alkali metals H. alkaline earth metals I. halogens

J. noble gases K. lanthanide series L. actinide series

Periodic Table IA

IIA IIIA IVA VA VIA VIIA

VIIIA

28

1. Aluminum ___________ 2. Calcium ___________ 3. Chromium ___________ 4. Helium ___________ 5. Lead ___________ 6. Mercury ___________ 7. Radium ___________ 8. Potassium ___________ 9. Sodium ___________ 10. Tin ___________ 11. Argon ___________ 12. Sulfur ___________ 13. Nitrogen ___________ 14. Iodine ___________ 15. Hydrogen ___________ 16. Krypton ___________ 17. Cobalt ___________ 18. Radon ___________ 19. Lithium ___________ 20. Gold ___________ 21. Xenon ___________ 22. Rubidium ___________ 23. Strontium ___________

24. Zinc ___________ 25. Barium ___________ 26. Cesium ___________ 27. Copper ___________ 28. Cadmium ___________ 29. Magnesium ___________ 30. Neon ___________ 31. Phosphorus ___________ 32. Silicon ___________ 33. Bromine ___________ 34. Tungsten ___________ 35. Beryllium ___________ 36. Carbon ___________ 37. Boron ___________ 38. Chlorine ___________ 39. Fluorine ___________ 40. Iron ___________ 41. Manganese ___________ 42. Nickel ___________ 43. Platinum ___________ 44. Silver ___________ 45. Antimony ___________ 46. Titanium ___________

DIRECTIONS: Fill in the blanks with the correct symbol for each element. You are responsible for knowing all 46 of the following elements (spelling counts) and their symbols.

29

Name ______________________________________________________ Period ____________ Are you an Element Expert?

Using a lap top, log onto the following web site to check your knowledge of the elements. http://education.jlab.org/itselemental/ ~ scroll down to “on-line” games

1. “Element Flash Cards”

a. Select, “More Options Please” b. Select:

Strange Symbols First 20 Elements First 36 Elements

Alkali Metals Alkaline Earth Metals Halogens

Noble Gases Lanthanides Actinides

Transuranic Elements Naturally Occurring Elements

Artificially Produced Elements

All Solids All Liquids All Gases

How many questions would you like?

5

10

20

40

All Available

What would you like to be tested on?

Chemical Names

Chemical Symbols

Atomic Numbers

Require that chemical symbols be properly capitalized?

Yes

No

c. Complete all forty flash cards.

2. Element Hangman a. Please complete 10 hangman questions and write the clue and answer below

Clue Answer

1. __________________________________________________________ ____________________

2. __________________________________________________________ ____________________

3. __________________________________________________________ ____________________

4. __________________________________________________________ ____________________

5. __________________________________________________________ ____________________

6. __________________________________________________________ ____________________

7. __________________________________________________________ ____________________

8. __________________________________________________________ ____________________

9. __________________________________________________________ ____________________

10. __________________________________________________________ ____________________

30

3. Element Crossword Puzzles a. Please complete all 9 crosswords and fill in below

Puzzle 1 ~ It's a Gas!

Across

2.

This gas can be used to fill party balloons.

4.

This gas is used to make yellow-green 'neon' signs.

6. This gas is widely used in luminous signs.

7. Nearly 1% of the earth's atmosphere is...

9. About 21% of the earth's atmosphere is...

10. Most of the visible universe is made of...

11. This gas is used in strobe lights.

Down

1.

When combined with tin, this gas helps keep your teeth strong.

3. This gas helps keep swimming pools clean.

5. About 78% of the earth's atmosphere is...

8. A radioactive gas.

Puzzle 2 ~ Easy Symbols

Across

2. This element's chemical symbol is He.

3. This element's chemical symbol is N.

6. This element's chemical symbol is C.

9. This element's chemical symbol is I.

10. This element's chemical symbol is U.

Down

1. This element's chemical symbol is Li.

4. This element's chemical symbol is Ne.

5. This element's chemical symbol is Al.

7. This element's chemical symbol is Ar.

8. This element's chemical symbol is O.

31

Puzzle 3 ~Strange Symbols

Across

1.

This element's chemical symbol is Na.

3.

This element's chemical symbol is Sb.

5.

This element's chemical symbol is Sn.

6.

This element's chemical symbol is Au.

8.

This element's chemical symbol is K.

9.

This element's chemical symbol is Pb.

Down

2.

This element's chemical symbol is Fe.

4.

This element's chemical symbol is W.

7.

This element's chemical symbol is Ag.

Puzzle 4 ~Known to the Ancients... Across

3.

Too soft for most tools, early people learned that this metal could be strengthened if it was alloyed with tin or zinc.

4.

The ancient Romans used this metal to make water pipes.

5.

Brass, a corrosion resistant alloy, is a mix of copper and this metal.

8.

The ancient Egyptians made black eye make-up with this element.

9.

A pale yellow material, this element can be found near volcanoes and hot springs.

11.

The cheapest and most abundant of all metals, people have been using this element for at least 5,000 years.

Down

1.

This liquid metal has been found in 3,500 year old Egyptian tombs.

2. Commonly found as coal or soot.

6.

Although known to the ancients, this metal was often confused with lead and tin.

7.

A soft, valuable metal, its purity is measured in carats.

9.

Frequently used in jewelry, this metal is the best conductor of heat and electricity.

10.

Bronze, the first alloy created by people, is a mix of copper and this metal.

32

Puzzle 6 ~The Alkaline Earth Metals

Across

2.

Two of this element's compounds burn with a red flame and are used in fireworks and signal flares.

4.

A fair amount of this element can be found in your bones.

5.

One of this element's compounds is used to produce X-ray images of the intestinal tract.

6. This element burns with a brilliant white light.

Down

1.

The first member of this group, this element can be used as a neutron source.

3. All isotopes of this element are radioactive.

Puzzle ~ 5 The Alkali Metals

Across

2.

While normally shown at the top of this group, this element is not an alkali metal.

4.

This alkali metal joins with a member of the halogen group to form table salt.

6. This element's chemical symbol is Rb.

7. The first member of the alkali metals.

Down

1.

This element's chemical symbol comes from the Latin word for alkali, kalium.

3.

This element, which is used in atomic clocks and photocells, melts at temperatures slightly above room temperature.

5.

The last member of this group, all isotopes of this element are radioactive.

33

Puzzle 7 ~The Chalcogen Group

Across

2.

The gas that you need to live.

4.

This element's resistance to the flow of electricity is greatly affected by the amount of light shining on it.

Down

1.

Named for the country of Poland, all isotopes of this element are radioactive.

3. This element's chemical symbol is Te.

4.

In its solid form, this element is pale yellow, brittle and odorless.

Puzzle 8 ~The Halogen Group

Across

4.

Discovered when too much sulfuric acid was accidentally added to seaweed ash.

5.

It is estimated that there is no more than 30 grams of this element in the earth's crust at any one time.

Down

1. This element is a liquid at room temperature.

2.

This element combines with an alkali metal to form table salt.

3. This is the most reactive of all elements

34

Puzzle 9 ~The Noble Gases

Across

1.

This element's name comes for the Greek word for hidden.

4.

This element makes up nearly 1% of the earth's atmosphere.

6.

Ions of this element were used as a propellant aboard the space probe Deep Space 1.

Down

2.

This element is the fourth most abundant element in the universe.

3.

This radioactive gas sometimes seeps into and accumulates in houses.

5.

The first member of the Noble Gases, this element is the second most abundant element in the universe.

35

Unit 2 ~ Problem Set #2 pg. 181-184; #28, 29, 31, 33, 48, 49, 71 28. Identify each property below as more characteristic of a metal or nonmetal.

a. a gas at room temperature ________________

b. brittle ________________

c. malleable ________________

d. poor conductor of electric current ________________

e. shiny ________________

29. In general, how are metalloids different from metals and nonmetals?

___________________________________________________________________________________ ___________________________________________________________________________________

31. Circle the elements that are representative elements: Na, Mg, Fe, Ni, Cl 33. Which of these metals isn’t a transition metal? a. aluminum b. silver c. iron d. zirconium 48. Write the symbol of the element or elements that fit each description.

a. a nonmetal in Group 4A. ________________

b. the inner transition metal with the lowest atomic number. ______________

c. all of the nonmetals for which the atomic number is a multiple of five. _______________________

d. a metal in Group 5A. ________________

49. In which pair of elements are the chemical properties of the elements most similar? Explain your

reasoning. a. sodium and chlorine b. nitrogen and phosphorus c. boron and oxygen

___________________________________________________________________________________ 71. Identify each process as a chemical or physical change.

a. melting of iron ________________

b. lighting a match ________________

c. grinding corn ________________

d. souring of milk ________________

36

Unit 2 ~Problem Set #3

pg. 61; #1-11 1. Which of the following is not a chemical change? a. paper being shredded b. steel rusting c. charcoal burning d. a newspaper yellowing in the sun 2. Which phrase best describes an apple? a. heterogeneous mixture b. homogeneous compound c. heterogeneous substance d. homogeneous mixture 3. Which element is paired with the wrong symbol? a. sulfur, S b. potassium, P c. nitrogen, N d. calcium, Ca 4. Which of these properties could not be used to distinguish between table salt and table

sugar? a. boiling point b. melting point c. density d. color 5. The state of matter characterized by a definite volume and an indefinite shape is a a. solid b. liquid c. mixture d. gas (A) Compound (B) heterogeneous mixture (C) element (D) homogeneous mixture 6. air - ______________________________ 7. carbon monoxide ______________________________ 8. zinc ______________________________ 9. mushroom pizza ______________________________ 11. Magnesium metal burns vigorously in oxygen to produce the compound magnesium oxide.

Use the law of conservation of mass to identify the masses labeled a, b, and c in the table.

Mass of magnesium (g)

Mass of oxygen(g)

Mass of magnesium oxide (g)

5.0 3.3 8.3

6.5 (a) 10.8

13.6 9.0 (b)

(c) 12.5 31.5

a. ____________ b. ____________ c. ____________

37

The Bony Element

Learn how the periodic table is organized into groups, periods, and sections of metals, nonmetals and metalloids while searching for the “bony” element. Use the clues below to identify an element. Find the element in the word search area and circle separately each letter in the element’s name. At the end of the clues, the un-circled letters, in order, will reveal the “bony element.

Clues

1. The metal in period 6, group 1. _____________________________

2. Transition metal in period 4, group 5. _____________________________

3. Alkali metal in period 3 that could be used to blow up a tub of water. _____________________________

4. Transition metal worth five cents. _____________________________

5. The yellow powdery nonmetal in group 16. _____________________________

6. Noble gas used in bright lights. _____________________________

7. The type of element found on the left side of the periodic table. _____________________________

8. The last naturally occurring element on the periodic table. _____________________________

9. The metalloid member of the halogen family. _____________________________

M G E R M A N I U M E S E N A G N A M U L I T H I U M C M U I R U L L E T U I S U R O H P S O H P B R O M I N E I S E L E N I U M M U N E D B Y L O M N S B E R Y L L I U M M U N I M U L A R A M A G N E S I U M N E G O R T I N O H M U I P O R U E P O T A S S I U M F M U I N I L O D A G A N T I M O N Y I C A R B O N C E S I U M M U I M S O L N E G Y X O V A N A D I U M Z I N C A T U N G S T E N E O N N I C K E L M C R S T A S T A T I N E A D U B N I U M E I L X B N R A D I U M O L D C I I U P L A E O O A M E T A L S U L F U R I P V B N R G D U R A N I U M O T U A B O E O O O R O M E R C U R Y G I M B R C R C N N A N M U I N I E T S N I E E

38

10. The alkaline earth metal with the largest atomic number. _____________________________

11. The metal in period 7, group 5. _____________________________

12. Liquid metal at room temperature. _____________________________

13. Most expensive metal in group 11. _____________________________

14. Transition metal whose symbol is derived from its Latin name, wolfram. _____________________________

15. Radioactive noble gas found in some homes. _____________________________

16. Alkaline earth metal found in period 6. _____________________________

17. Only nonmetal in group 14. _____________________________

18. Statue of Liberty is made of this transition metal. _____________________________

19. Period 5 transition metal used in jewelry. _____________________________

20. Noble gas in period 5. _____________________________

21. Metalloid with the lowest atomic number. _____________________________

22. The third noble gas. _____________________________

23. The first metal in group 9. _____________________________

24. Second lanthanide metal that begins with the letter E. _____________________________

25. Only member of the actinide series that begins with the letter E. _____________________________

26. First metal found in the carbon family. _____________________________

27. Last transition metal in period 4. _____________________________

28. The last naturally occurring transition metal in group 8. _____________________________

29. Inner transition metal that begins with the letter G. _____________________________

30. Metalloid whose symbol is derived from its Latin name, stibium. _____________________________

31. Artificially made metal in group 8. _____________________________

32. The metal in the actinide series named after a state bordering the Pacific Ocean. _____________________

33. Metal found in the lanthanide series that is named after a continent. _____________________________

34. First alkali metal found in the same row as transition metals. _____________________________

35. Diatomic element found in group 15. _____________________________

36. First alkaline earth metal. _____________________________

37. Representative element that produces a very bright white light when burned. _______________________

38. First metal in the boron family. _____________________________

39. Fifth transition metal. _____________________________

40. First nonmetal in period 4. _____________________________

41. The metal in group 6, period 5. _____________________________

42. Second nonmetal in the nitrogen family. _____________________________

43. Only liquid nonmetal at room temperature. _____________________________

44. The heavier metalloid in the carbon family. _____________________________

45. First metal on the periodic table. _____________________________

46. Metalloid in the oxygen family. _____________________________

47. Diatomic element that makes up 20% of air. _____________________________

The “Bony” Element is ___________________________

39

Name _______________________________________ Period _______________

Periodic Table Puns DIRECTIONS: Use your imagination and the elements in the PT to solve each pun! Write the name of the element and the symbol on the appropriate blanks. Example: Five cents – Nickel, Ni

1. What you do in a play _____________________________ __________

2. What you do to a wrinkled shirt _____________________________ __________

3. “Tasty” part of your mouth _____________________________ __________

4. Police _____________________________ __________

5. Name of a goofy convict _____________________________ __________

6. What you do to flowers _____________________________ __________

7. Extinct _____________________________ __________

8. This man followed the yellow brick road _____________________________ __________

9. What a doctor does to his patients _____________________________ __________

10. Your brother or mine _____________________________ __________

11. What a dog does with a bone _____________________________ __________

12. What a cloud does _____________________________ __________

13. A boring person _____________________________ __________

40

Element Practice Quiz DIRECTIONS: Provide either the correctly spelled name or symbol for the following elements.

1. Potassium __________

2. Sodium __________

3. Rubidium __________

4. Radon __________

5. Mercury __________

6. Nitrogen __________

7. Radium __________

8. Helium __________

9. Strontium __________

10. Lithium __________

11. Aluminum __________

12. Argon __________

13. Lead __________

14. Calcium __________

15. Xenon __________

16. Cobalt __________

17. Tin __________

18. Sulfur __________

19. Chromium __________

20. Hydrogen __________

21. Krypton __________

22. Iodine __________

23. Gold __________

24. Ti ______________________________

25. Ag _____________________________

26. Ni _____________________________

27. Fe ______________________________

28. Cl ______________________________

29. B ______________________________

30. W ______________________________

31. Br ______________________________

32. P ______________________________

33. Mg ______________________________

34. Cu ______________________________

35. Ba ______________________________

36. Sb ______________________________

37. Pt ______________________________

38. Mn ______________________________

39. F ______________________________

40. Zn ______________________________

41. C ______________________________

42. Be ______________________________

43. Si ______________________________

44. Ne ______________________________

45. Cd ______________________________

46. Cs ______________________________

41

The Power of Observation Seeing Is Believing

INTRODUCTION:

Good scientists make detailed observations. In this

experiment, you are going to observe some

chemical and physical changes and then use your

observations to answer some questions.

The observations that you make are for your

use, so it is important to clearly state exactly what

you see so that you can draw conclusions from

these observations. Be specific, because in order

to make hypotheses you can use only your

explanations of what happened in the reaction.

MATERIALS:

goggles stirring rod

spoon 2 beakers (100 or 150-mL)

crystals X 100-mL graduated cylinder

liquid Y metal foil

liquid Z

OBJECTIVES:

1. to observe changes in matter

2. to make detailed observations to answer

questions about the changes in matter.

PROCEDURE:

1. Obtain one-half of a spoonful of crystals X and

place them in the clean, dry 100 or 150-mL

beaker. Caution: These crystals are harmful if

ingested; do not eat them. Avoid contact and

rinse spills with plenty of water.

2. Using a graduated cylinder, measure 25 mL of

liquid Y.

3. Add the 25 mL of liquid Y to the beaker

containing crystals X. Do not stir. Observe the

beaker for about three minutes.

4. Stir the crystals and liquid Y until the solid

completely dissolves.

5. Obtain a piece of metal foil approximately 4

cm by 4 cm.

6. Loosely crumple the metal foil and place it into

the beaker with the dissolved crystals. If the

foil floats, submerge it with a stirring rod.

Allow the reaction to sit while you complete

steps 7 and 8.

7. Using a graduated cylinder, measure 25 mL of

liquid Z and place it into a clean 100 or 150‑-

mL beaker. Caution: Liquid Z is dangerous.

Please handle with care. Notify the instructor

if a spill occurs.

8. Obtain a second piece of metal foil the same

size as in step 5. Crumple the foil and place it

in liquid Z. The reaction starts slowly, so allow

enough time for the reaction to go to

completion. Discard the liquid into the sink.

9. Observe the reaction from step 6. Decant the

liquid into the sink, place the solid in the trash

can, and rinse the beaker with water.

CONCLUSION:

When steps 1-9 of the procedure are

completed, obtain a series of questions from

your instructor about the lab. Use your

observations to answer the questions in the

section titled “Conclusion” in your lab report.

42

Names __________________________________________________________________ Period __________

Observations

1. ___________________________________________________________________________________________

2. ___________________________________________________________________________________________

3. ___________________________________________________________________________________________

4. ___________________________________________________________________________________________

5. ___________________________________________________________________________________________

6. ___________________________________________________________________________________________

7. ___________________________________________________________________________________________

8. ___________________________________________________________________________________________

9. ___________________________________________________________________________________________

Conclusions

1. ___________________________________________________________________________________________

___________________________________________________________________________________________

2. ___________________________________________________________________________________________

___________________________________________________________________________________________

3. ___________________________________________________________________________________________

___________________________________________________________________________________________

4. ___________________________________________________________________________________________

___________________________________________________________________________________________

5. ___________________________________________________________________________________________

___________________________________________________________________________________________

6. ___________________________________________________________________________________________

___________________________________________________________________________________________

43

Investigating the Evidence of Chemical Changes

INTRODUCTION: A good understanding of materials around us requires some knowledge of the chemical and physical characteristics of matter. Physical properties of a substance are those properties that can be measured and observed without altering the chemical composition of the substance. Examples are color, boiling point, hardness, and density. Because they do not change the chemical composition, physical properties can be used to identify a substance. Physical properties, such as density and freezing point, do not depend on how much matter is measured; these are intensive properties. Those that depend on the amount of matter, such as mass and volume, are extensive properties. Substances may undergo physical changes, which may change the substance’s appearance but do not change its chemical makeup. For example, freezing water changes its familiar liquid form into ice, a solid which can be easily broken; it is still water, however, in the chemical sense, since its chemical composition has not changed. Chemical properties of a substance are those that it exhibits when it undergoes a change in composition. This change is often brought about by contact with another substance. Examples are iron rusting (Fe changing to Fe2O3), carbon burning (C changing to CO2), and aluminum corroding (Al changing to AlCl3). Whenever a substance’s composition is altered, a chemical

change has taken place.

OBJECTIVES:

1. To observe evidence that a chemical reaction

may have occurred.

2. To learn how to write specific observations.

3. To deduce an answer from a collection of

data.

MATERIALS:

sodium bicarbonate, NaHCO3 _________________

calcium chloride, CaCl2 _______________________

phenol red solution __________________________

1 small test tube paper towels

1 Ziploc bag distilled water

PROCEDURE:

1. Using a Ziploc bag as your reaction vessel, mix as many combinations of the four substances as possible. Record in the data table the combination of chemicals mixed and what changes were produced. You are looking for four particular changes: color change, exothermic reaction, endothermic reaction, and production of a gas.

a. When adding solids to the bag, use approximately two teaspoons.

b. When adding liquid to the bag, fill a small test tube, place it in the bag upright, squeeze the air out, seal the bag, and then invert to mix.

c. Remember to wash and dry your bag after each trial.

CONCLUSION: 1. Using your observations, list the minimum

substances necessary to produce each of the following chemical changes:

a. color change b. exothermic reaction c. endothermic reaction d. production of a gas

Note: Neatness counts in all your lab reports. If you cannot write legibly, then you will have to learn how to type. The only excuse for sloppiness is laziness, which is not acceptable. If I cannot read it, it is wrong!

It’s All In the Bag

44

Names__________________________________________________________________ Period __________

OBSERVATION TABLE

Substances Mixed

Observations

Color change _____________________________________________________________________

Exothermic Reaction _____________________________________________________________________

Endothermic Reaction _____________________________________________________

Production of gas _____________________________________________________________________

45

An Investigation of Physical and Chemical Changes

INTRODUCTION: A good understanding of materials around us requires some knowledge of the chemical and physical characteristics of matter. Because no two substances have the same combination of chemical and physical properties under identical conditions, these properties can be used to identify a substance. In this experiment, you will examine a variety of substances and then cause some changes to take place. Based on observations and the results of the tests you perform, you will decide whether these changes are chemical or physical in nature. MATERIALS: magnesium ribbon aluminum sodium bicarbonate sodium chloride sand (silicon dioxide) sucrose 6M hydrochloric acid (HCl) copper II chloride EQUIPMENT: test tubes glass stirring rod 2 beakers graduated cylinders funnel filter paper ring stand wire gauze iron ring evaporating dish Bunsen burner tongs watch glass test tube rack small metal cup or foil boat PROCEDURE: Causing a Chemical or Physical Change

Obtain seven small sheets of paper. Label each with the name of a solid from the materials listed above. Obtain two pieces of magnesium and one small square of aluminum foil; place them on the appropriately labeled pieces of paper. Using a clean plastic spoon, transfer a PEA size sample of each of the other solids to the appropriately labeled pieces of paper. 1. Fill a large test tube about one-fourth full of

tap water. Add the sample of copper II chloride to the water. Stir the mixture with your glass stirring rod until the crystals are completely dissolved. Record your observations in Table I.

2. Loosely crumple the aluminum foil sample into a ball. Place the ball of aluminum into the copper II chloride solution. Let the mixture sit until the end of the lab period; then record all of your observations in Table I, change # 2. Pour the liquid contents of the test tube down the sink; discard the solid material in the trash can.

3. CAUTION: Do not look at burning magnesium. Its flame is very bright and can damage your eyes. Keep burning magnesium at arm's length at all times and do not inhale the fumes that are given off. Place a watch glass on the laboratory table close to your burner. Light the burner. Using crucible tongs to hold ONE strip of magnesium ribbon, place the strip in the Bunsen burner until the magnesium ignites. Position the magnesium so that the product (and only the product) of the combustion falls onto the watch glass. Do not drop any unburned magnesium onto the watch glass; throw it into the trash can. Compare the appearance of the product with that of the original magnesium ribbon. Record your observations in Table I, change # 3.

4. CAUTION: Hydrochloric acid (HCl) is corrosive. If you spill any on your clothing or skin, wash immediately with water. Transfer the product of step 3 (make sure no unburned Mg goes into the test tube) from the watch glass to a clean, dry test tube. Add 10 drops of 6M HCl to the test tube. Feel the bottom of the test tube and observe any changes in the solid. Record your observations in Table I. Wash the contents of the test tube into the sink.

5. Place the 2ND, unburned strip of magnesium

into a clean, dry test tube. Add 10 drops of 6M HCl to the test tube. Feel the bottom of each test tube and observe any changes in the solid. Record your observations in Table I. Pour the liquid in the test tube into the sink. If there is any unreacted Mg, throw it in the trash can.

What’s the Matter?

46

6. Place the baking soda (which is also called sodium bicarbonate or sodium hydrogen carbonate) into a small test tube. Add 10 drops of 6M HCl (hydrochloric acid) and observe. Make sure you feel the bottom of the test tube. Record your observations in Table I.

7. Combine the samples of sodium chloride and sand on a clean piece of paper. Examine the mixture and record your observations in Table I.

8. Transfer the salt-sand mixture to a clean 150-

mL beaker. Add 30 mL of tap water and stir the mixture with your glass stirring rod. Record your observations in Table I.

9. Filter the mixture as follows:

a. Fold a piece of filter paper as shown below:

b. Place the filter paper in the glass funnel; moisten with a small amount of water. Press the moistened paper against the funnel to seal it.

c. Set up your ring stand and attach the small iron ring. Place the funnel in the iron ring to support it.

d. Place a 150 mL beaker below the funnel. Make sure that the mouth of the funnel is inside the beaker and touching the side of the beaker.

e. Pour the salt-sand-water mixture into the funnel, making sure the liquid level never totally fills the filter paper. The liquid that passes through the filter paper and is collected in the beaker is called the filtrate.

f. Examine the wet residue on the filter paper and record your observations in Table I.

10. Pour 10 mL of the filtrate into an evaporating dish. Set the dish on a wire gauze supported by an iron ring attached to the ring stand. Using a Bunsen burner, heat the dish gently until the liquid almost evaporates. Turn off the Bunsen burner and allow the last bit of water to evaporate on its own. Examine the dry residue in the evaporating dish and record your observations in Table I. Discard the filter paper in the waste can. After the evaporating dish has been cooled, the filtrate and residue in the dish may be washed down the sink.

11. Obtain an aluminum pan/boat from the central

distribution table. Place half of the sucrose sample into the aluminum pan. Place the pan containing the sugar on a hot plate that has been preheated to 250° C and heat for one minute. Observe any changes in the sugar; record your observations in Table I.

12. Place the other half of the sucrose sample in

the same pan and place on the wire gauze supported by a ring stand and iron ring. (You do NOT have to discard the sample from step 11.) Heat strongly with a Bunsen burner. Use tongs to periodically remove the pan from the wire gauze and check for any odor generated. (Never check for odor while heating.) Record your observations in Table I. After the pan has cooled, throw it in the trash can.

CONCLUSION: For each of the 12 changes you observed, fill in Table II. Indicate whether it was a physical change by writing P or chemical by writing C in the second column. In the last column of Table II, cite the specific evidence for each of your choices. Some examples of evidence (observations) of a chemical change are the following: • a color change • production of a gas • production of heat or light. This list is not conclusive. You CANNOT state that a new substance was formed because this is a hypothesis, not an observation.

FOLD FILTER PAPER IN HALF

FOLD INTO HALF AGAIN

1. 2.

3.

OPEN CONE

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Names__________________________________________________________________ Period __________

TABLE I ~ What’s the Matter

Change # Observations

1

2

3

4

5

6

7

8

9

10

11

12

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Names__________________________________________________________________ Period __________

TABLE II ~ What’s the Matter

Change # C or P? Evidence

1

2

3

4

5

6

7

8

9

10

11

12

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WHAT dO I need to know?? Unit 2: Matter, Energy, & the Periodic Table

Matter tree

o Homogeneous

Solution

Pure substance

Element

compound

o Heterogeneous

Mixture

Properties of metals/nonmetals

Evidence of chemical/physical changes

Organization of the periodic table

Diatomic elements (Br2, I2, N2, Cl2, H2, O2, F2)

Vocabulary

o i.e. group, period, precipitate, malleable, solid, liquid,

gas, matter tree, etc.

Law of Conservation of Mass

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