c h a p t e r 1 c h e m i s t r y 1 a p a g e | 1...

C h a p t e r 1 C h e m i s t r y 1 A P a g e | 1

Beginning:

Materials: Chemistry: A Molecular Approach, Tro, 4th edition, Pearson, 2017,

Chem 1B Lab Manual, Dept. of Chemistry at Moorpark College,

Safety Glasses, and Scientific Calculator with exponential and logarithmic

functions (no cell phones, graphing, programmable, alpha typing calculators

allowed during tests/quizzes) MasteringChemistry access code (access to

online assignments, e-book, tutorials, powerpoints, etc.)

How to start: Review the math found in Appendix. If the math in Appendix is difficult to

follow, consider taking more algebra before attempting Chemistry 1A. It is

expected that students in Chemistry 1A have a background in chemistry;

therefore the material is covered quickly and intensely. Read, study and work

problems often and regularly to keep up. Look over materials and websites.

Notice the appendices I-IV and glossary in the textbook as well as resources

in MasteringChemistry. We cover Chapters 1-13 in Chemistry 1A. When

starting a new Chapter read the contents (section titles) found on the first page

of the chapter, chapter in Review at the end. After you have a general

overview of the upcoming material read the chapter text before coming to

lecture and a second time after the material is covered in lecture. Work out

the examples and problems and work a variety of the end of chapter

homework problems for practice and greater understanding.

Syllabus: Refer to the syllabus often to know the class expectations, laboratory

activities (experiments, formal lab write-ups, and workshops), test days, etc.

More help: Your instructor has office hours set aside each week for assistance. The

learning center in the library often has tutors that may help in math and chemistry. It

is recommended that you exchange co Look over the lab assignment before attending

the labs

ntact information with others in the class to assist in forming study groups, assist with

getting a ride to school when your car does not work, having someone to ask

a question regarding class, or after missing a class to find out what was

covered.


Chapter 1: Matter, Measurement and Problem Solving

Homework:

Read Chapter 1 and work out sample/practice exercises and end of chapter problems

for more practice.

Look over the lab assignment before attending the labs

Memorize the names (correct spelling) and symbols (capitalize only the first letter)

of the 44 common elements in the handout.

Register for and start the homework online through MasteringChemistry

Chemistry: The science that seeks to understand the behavior of matter by studying the

behavior of atoms, molecules and compounds. The study of the composition, properties,

and transformations of matter.

Matter: Anything that has mass and occupies space. Matter is composed of atoms,

molecules, and compounds

Atoms and Molecules: Matter, composition, structure, element, atom, molecule,

compound; chemical bonds. All things are made of atoms.

This image shows the Kanji for

“atom” written with

individual Fe atoms on top of Cu


The Scientific Method: A systematic procedure for solving problems and exploring

natural phenomena. Chemists employ the scientific method, which makes use of

observations, hypotheses, laws, theories, and experiments.

Observations (data; a series of measurements or observations)

o observations are the foundation of the scientific method

o Some observations are made with the naked eye, while others rely on

instrumentation.

o data can be qualitative descriptions or quantitative measurements.

o Scientific data may be graphed to see relationships.

o data is most useful when collected under controlled conditions, experiments

Hypotheses

o tentative explanations to interpret the observations

o a useful hypothesis must be testable

o must be rejected or corrected when they conflict with experiment

Experiments

o experiments must be repeatable and reproducible

Practical use of the Scientific Method…

Observation/Problem:

The lamp in the bedroom will not light/turn on.

Possible hypotheses:

Come up with some testable hypothesis from your experience

Experiments:

From each hypothesis, an experiment can be conducted to test the

hypothesis/explanation. More observations are obtained through experiments

and over time, a good hypothesis/explanation is repeatable and reproducible.

What experiments can be performed to check your hypothesis?


The cycle of the scientific method is repeated many times with rejections, alterations,

improvements and support. Numerous observations and experiments lead to Scientific

Laws and Theories.

Scientific Laws come from observations (also called natural laws)

compactly summarize patterns and results of a large number of observations

predicts future observations

may apply only under special conditions

are descriptions of nature that predict future outcomes, not explanations

A few examples of Natural Laws(also known as Scientific Laws or just Laws)…

1. Newton’s Laws of Motion

2. Dalton’s Law of Partial Pressures

3. Lavoisier’s Law of Conservation of Mass

Scientific Theories come from hypotheses

Are well-tested models that explain and give the underlying causes for

observations and laws.

Discarded or refined when they can't explain new experimental results

A good theory...

explains currently available data

is as simple as possible (but no simpler!)

accurately predicts results of future experiments

suggests new lines of work and new ways to think

clearly shows underlying connections

A few examples of Theories…

1. Heliocentrism (1543, Copernicus)

2. Evolution (1859, Darwin)

3. Quantum Theory (Max Planck, Einstein, Niels Bohr, Werner Heisenberg,

Erwin Schrödinger, Max Born, Paul Dirac, 1900–1926)


The Scientific Method (Do you understand it?)

1. A number of people become ill after eating dinner in a restaurant. Which of the

following statements is a hypothesis?

a) The cooks felt really bad about it.

b) Bacteria in the oysters may have caused the illness.

c) Everyone who ate oysters got sick.

d) Symptoms include nausea and dizziness

e) People got sick whether the oysters were raw or cooked

2. The Scientific Method

a) is just a theory

b) is a strict set of rules and procedures that lead to inarguable fact.

c) isn't used much in modern chemistry.

d) is based on continued observation and experiment.

e) is a framework for proving an argument you know to be true.

3. Which of the following statements is TRUE?

a) A scientific law explains an observation.

b) Once a theory is constructed, it is considered fact.

c) A hypothesis is speculation that is difficult to test.

d) An observation explains why nature does something.

e) A scientific law summarizes a series of related observations.

4. Classify each of the following as an observation (O), a law (L), or a theory (T)

_____ a) Matter is made of atoms

_____ b) Matter is conserved in chemical reactions

_____ c) When wood burns in a closed container, its mass does not change

_____ d) A body in motion stays in motion unless acted on by a force

_____ e) The universe began as a cosmic explosion called the Big Bang

_____ f) A stone dropped from 450 meters falls to the ground in 9.6 seconds.


Element: A fundamental substance that cannot be chemically changed or broken down

into anything simpler. All elements are made from stardust.

About 90 are naturally occurring. 75% of the observed mass of the universe is H

Percentage of Elements by Mass in the Earth

Percentage of Elements by Mass in the Human Body


Memorize the names (correct spelling) and symbols (capitalize only the first letter) of the

44 common elements in the handout.

Historical Notes: pottery and ceramics, glass, embalming, bronze age, metals,

Chinese (Yin, Yang), Greek (Earth, Wind, Fire, Water, Ether), alchemy, scientific method.

Periodic Table:

1789 French scientist Antoine Lavoisier first tabulated the known elements (24)

1829 Johann Dobereiner observed triads (Ca, Sr, Ba and Cl, Br, I and Li, Na, K), by

1843, sixteen triads were known.

1869 Russian chemist Dmitri Mendeleev placed elements in 7 horizontal rows

(Periods) and 18 vertical columns (Groups). Elements in a group behaved

similarly.

Main groups, transition metals, inner transition metals(rare earth metals)

Alkali metals, alkaline earth metals, halogens, noble gases

Metals, semimetals (metalloids), nonmetals


The Study of Chemistry:

Chemistry: The study of the composition, properties, and transformations of

matter.

1. Atomic and Molecular Perspective- Matter, composition, structure, element, atom,

molecule, compound,

2. Why Study Chemistry –Chemistry provides important understanding of our

world/universe and how it works. It is a very practical science that has improved

our daily lives. It is the foundation that provides the basic language required for

many other science and technological fields.

Classifications of Matter:

States of Matter:

solid liquid gas

Properties: (shape, volume, energy content, phase changes, endothermic vs.

exothermic).

Solids may be crystalline or amorphous


Pure Substances Pure substances have one invariable composition independent of how they

were formed.

elements (memorize the common elements and symbols for quiz)

molecules

compounds.

Mixtures:

Mixtures have a variable composition

Heterogeneous: composition varies from one region to another

Homogeneous: uniform composition


Separation Mixtures:

Different components have different physical or chemical properties which enable

separations.

Distillation:

Evaporation:

Decanting:

Filtration:

Chromatography: paper, liquid, gas


Properties of Matter:

1. Physical: A property or

change that does not change

the chemical composition

such as… change of state,

separation of mixtures

(decantation, filtration,

evaporation, distillation,

chromatography),

temperature, odor.

2. Chemical: A property or change that does

involve a change in the chemical makeup such

as… Elements to compounds, reactants forming a

different compound, change in chemical structure

and composition, rusting (oxidation of metals),

combustion, and decomposition.

3. Intensive: Property is independent of the

amount… density, melting point, color

4. Extensive: Property is dependent of the

amount… mass, volume, and length


Energy: Energy is the capacity to do work. Work is force applied across a distance,

push or pull on an object.

Energy can be converted from one form to another. When matter undergoes a

chemical or physical change, the amount of energy in the matter also changes.

Potential energy

Kinetic energy

Thermal energy is a form of

kinetic energy as the molecules

are moving.

Law of Conservation of Energy

Spontaneous processes prefer the direction that will lower energy


Units of Measurement:

SI Units (Systeme International d’Unites) chosen by international agreement in

1960 based on the metric system.

Physical Quantity Unit Abbreviation

Mass kilogram kg

Length meter m

Temperature Kelvin K

Amount mole mol

Time second s

Electric current ampere A

Luminous intensity candela cd

Volume (derived unit), dm3 liter L

Density (derived unit), mass/V kg/m3 Solid, liquid: g/cm3=g/ml,

for gases: g/L

Energy (derived unit), kgm2s-2 joule J

Prefixes used in the metric system.

Prefix Abbrev. Meaning Example

Giga G 109 1 Gigabyte = 1 x 109 bytes

Mega M 106 1 Megameter = 1 x 106 meter

kilo k 103 1 km = 1 x 103 m

unit - 1 1

deci d 10-1 10 dm = 1 m

centi c 10-2 102 cm = 1 m

milli m 10-3 103 mm = 1 m

micro 10-6 106 m = 1 m

nano n 10-9 109 nm = 1 m

pico p 10-12 1012 pm = 1 m


Know these Common Conversions. (more in textbook)

Length 2.54cm = 1 inch 1 km = 0.621 mi

Mass 453.6 g = 1 pound (lb) 1 kg = 2.205 pounds (lbs)

Volume 1 ml = 1 cm3 = 1 cc 946 ml = 1 qt

Temperature °C = K -273.15

K = (°C) + 273.15

°F = 1.8(°C) + 32

°C = [(°F) – 32]

1.8

Energy 4.184 J = 1 calorie 1.602 x 10-19 J = 1 eV

Temperature:

Derive the temperature

conversion formulas:

y = mx +b

Choose x as Celsius to have a

simple y intercept (b)


Uncertainty in Measurement:

Inexact (has uncertainty)

Exact (definitions: i.e. 1 ft = 12 in, or

whole items: i.e. number of

students enrolled)

Precision (measurements agree with

each other)

Imprecision in measurements may be

caused by random or systematic

errors.

Random error (no specific cause, cannot

be corrected)

Systematic error (caused by limitations

in technique, experimental design,

or instrument calibration, can be reduced)

Accuracy (measurement agrees with true value)

Significant Figures-only the last digit is estimated/uncertain.

What is your estimated reading for the graduated cylinder?

Rules for significant figures:

Exact numbers Unlimited

significance

1000mm = 1 m

Numbers 1 through 9 Significant 25.223 g

Leading zero Never significant 0.00402 kg

Captive zero between nonzero Significant 2.005 x 108 atoms

Trailing zero with decimal Significant 3.200 x 104 s

Trailing zero without decimal Uncertain 1400 miles

Significant Figures in Calculations:

1. Addition and Subtraction-minimum significant to the right taken

2. Multiplication and Division-least number of significant numbers


Rounding Numbers:

Remove all nonsignificant numbers. Less than 5 round down (drop it), when 5 or

more round up.

Scientific Notation: When writing very large or very small values it is best to remove the

placeholder zeroes and keep all the significant numbers. Scientific notation keeps one

digit before the decimal, remaining significant figures after the decimal, and multiplies by

a factor of ten (negative power for small munbers and positive for large numbers.

?.??? x 10?

12,300,000 min = 1.23 x 107 min 0.000 000 000 765 m = 7.65 x 10-10 m

Dimensional Analysis:

Aids problem solving using conversion factors/definitions

1. Always write every number with its unit

2. Always include units in calculations

3. Use conversion factors to generate equivalence statements

4. Arrange conversion factors to cancel starting units

5. May string conversion factors together

6. When squaring a conversion factor one must square both the number and unit, When

cubed, number and unit must be cubed

7. Round off at the final step, do not round progressively

8. Sort, Strategize, Solve, Check

Practice Problems:

1. One lead has a mass of 0.000 000 000 000 000 000 000 3441 g. Express this in

proper scientific notation.

2. Indicate the number of significant figures in each and write in Scientific Notation.

a) 0.000343 km

b) 645,000,000 ml


3. Convert 8.22 x 102 nanoliters/min into units of quarts/year.

4. The average surface temperature of the South Pole is -56C.

a) What is this temperature in Kelvin?

b) What is this temperature in Fahrenheit?

5. A student finds that the weight of an empty beaker is 53.583 g. She places a solid in

the beaker to give a combined mass of 57.483 g. To how many significant figures is

the mass of the solid known?

6. A 3.00 quart container weighs 302 grams when empty. When it is filled with liquid,

the container weighs 2.412 kilograms. What is the density of the liquid in g/ml?

7. Describe the difference between experimental data which is accurate and data which

is precise. Give examples. What is the difference between random and systematic

errors?


8. Place a P before a physical property or change and a C before a chemical property

or change:

The reaction with zinc and hydrochloric acid to produce a gas

Crystallization of CuSO4 by evaporation of its aqueous solution

Metals are shiny, malleable, ductile, good conductors of heat and electricity

Alkali metals combine with halogens in a 1:1 ratio to form a compound

9. For the following identify each in as many ways as possible using the following:

a) matter, b) pure substance, c) compound, d) molecule, e) element

f) homogeneous mix g) heterogeneous mix h) metal i) nonmetal

j) ionic compound k) alloy n) none

a) Oxygen, O2

b) Sodium bromide, NaBr

c) Cu-Zn alloy called brass

d) Burrito

e) Potassium

f) Hypothesis

10. Monel metal is a corrosion-resistant copper-nickel alloy used in the electronics

industry. A particular alloy with a density of 8.70 g/cm3 and containing 0.024%

silicon by mass is used to make a rectangular plate that is 30.0 cm long, 17.0 cm

wide and 3.00 mm thick.

What is the volume of the alloy?

What is the mass of the alloy?

What is the mass of just the silicon in the sample?


Practice Problems: (ANSWERS)

1. 3.441 x 10-22 g

2. a) 0.000343 km 3.43 x 10-4km

b) 645,000,000 ml 6.45 x.108 ml

3. 0.457 quarts/year.

4. a) 217 Kelvin

b) -69 ˚F

5. 3.900 g; answer has 4 significant figures

6. 0.743 g/ml

7. Precision (measurements agree with each other). Accuracy (measurement agrees

with true value). You may want to check the weight of a suitcase so you will not be

charged extra for too much baggage before going on an airline flight. You may

weigh your suitcase on the same bathroom scale several times and find the numbers

agree with each other (precision). If the bathroom scale always reads 5 pounds

lighter that the true value you will not be accurate and possible pay the extra fee.

That bathroom scale has a systematic error that may be fixed with calibration.

8. C The reaction with zinc and hydrochloric acid to produce a gas

P Crystallization of CuSO4 by evaporation of its aqueous solution

P Metals are shiny, malleable, ductile, good conductors of heat and electricity

C Alkali metals combine with halogens in a 1:1 ratio to form a compound

9. a) Oxygen, O2 a, b, d, e, i

b) Sodium bromide, NaBr a, b, c, j,

c) Cu-Zn alloy called brass a, f, k

d) Burrito a, g

e) Potassium a, b, e, h

f) Hypothesis n

10. a) 153 cm3 volume

b) 1330 g mass alloy

c) 0.32 g mass of just the silicon

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