Name:

IB Chemistry Summer Assignment

Summer 2014 This packet is due the first day of class.

(HW completion)

Special thanks to Mr. Turner of RMHS!

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NAMES AND CHARGES OF COMMON IONS Reference Information

MONATOMIC IONS

Group 1 +1

Group 2 +2

Group 3 +3

Group 5 -3

Group 6 -2

Group 7 -1

Li+ Be2+ B3+ N3- O2- F-

Na+ Mg2+ Al3+ P3- S2- Cl-

K+ Ca2+ Ga3+ Br-

Rb+ Sr2+

I-

Cs+ Ba2+

Transition Metals: Many can form more than one monatomic ion

cadmium Cd2+ gold Au

chromium Cr3+ mercury (I) Hg 2+ and (II) Hg2+

cobalt Co2+ and Co3+ nickel Ni2+

copper Cu+ and Cu2+ silver Ag+

iron Fe2+ and Fe3+ titanium Ti2+ , Ti3+ and Ti4+

lead Pb2+ and Pb4+ tin Sn2+ and Sn4+

manganese Mn2+ zinc Zn2+

POLYATOMIC IONS

+1 -1 -2 -3 ammonium NH +

4

acetate CH COO-

3 carbonate CO 2-

3

phosphate PO 3-

4

chlorate ClO3- chromate CrO 2-

4

chlorite ClO2- dichromate Cr O 2-

2 7

cyanide CN- oxalate C O 2-

2 4

hydroxide OH- peroxide O 2-

2

hypochlorite ClO- silicate SiO 2-

3

iodate IO3- sulfate SO 2-

4

nitrate NO3- sulfite SO 2-

3

nitrite NO2- thiosulfate S O 2-

2 3

perchlorate ClO4-

permanganate MnO4-

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TOPIC 1. SCIENTIFIC MEASUREMENTS AND CALCULATION SKILLS • Know from memory the 7 base SI units (name and symbol) • Know from memory the SI prefixes (symbol and multiplier) from giga down through nano

• Know from memory the SI derived units for density, volume, concentration, pressure & energy

• Know the definitions of accuracy vs. precision, and how to calculate percent error. • Be able to apply the rules for significant digits: writing, rounding and calculating

• Be able to inter-convert units using dimensional analysis (sometimes called the factor label or

“picket fence” method)

• Be able to express numbers and do calculations using scientific notation.

• Be able to manipulate logarithms and inverse logarithms on your calculator (remember pH?).

PROBLEMS: 1. How many significant digits are shown in each of these measurements?

a. 27.3 g _________ e. 65.089 g

__________

b. 0.013 cm

c. 16.30 mL

_________ f. 23.00m

_________ g. 100.78 kg

__________

__________

d. 0.0005 moles ________ h. 0.01050M __________

2. Perform the following conversions. Round answers to the correct number of significant digits and express in

scientific notation.

a. 0.19 km to cm ________________ f. 105.9 Ms to s___________________

b. 5.75 g to kg ________________ g. 2.400 mm to m ___________________

c.

25.0 mL to L ________________

h. 1.606 kg to mg

___________________

d. 7.450 g to mg ________________ i. 2.70 g/cm3 to kg/m3___________________

e. 6.50 x 102 nm to m ________________ j. 125 mL to dm3 ___________________

3. Write these numbers in scientific notation and round to the given number of “sig figs”:

a. 15,678 m (3 sig figs) _____________

b.

c.

d.

0.001278

6,000 g

0.09809m

(2 sig figs)

(4 sig figs)

(3 sig figs)

_____________

_____________

_____________

4. A student measures a small piece of aluminum foil. The length is 8.252 cm, and the width is 3.44 cm. She should

report the area of the foil as ______________________. If the aluminum foil were precut by industrial machines

using high precision, the actual area should have been 11.75 cm2, what was the student’s percent error? Also, convert

to m2.

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5. Calculate, using sig figs: a) (8.753 x 10-13) (5.5 x108)

6.022 x 1023

b) (8.753 x 10-12) - (5.5 x10-13)

6.022 x 1023

6. The SI unit for gas pressure is the Pascal (Pa), equal to a force of 1 Newton acting on a surface of 1m2.

Since the Pascal is a very tiny unit of pressure, we usually use kiloPascals, or kPa. However, non-SI units are also used:

atmospheres (atm), mm Hg, and torr. The conversion factors are:

1 standard atmosphere (atm) = 101.3 kPa = 760 mm Hg = 760 torr.

Complete the the following conversions:

a. 745 mm Hg to kPa ___________ c. 235 kPa to atm __________________

b. 87 mm Hg to atm ____________ d. 5.00 atm to torr __________________

SHOW ALL WORK USING DIMENSIONAL ANALYSIS; UNDERLINE/ BOX ANSWERS.

7. A pile of chemistry books used over the summer to prepare for IB chemistry weighs 158.0 lbs. If 1 kg = 2.204 lbs,

what is the mass of this pile of knowledge in milligrams?

8. Take your height in inches, and convert it to your height in kilometers.

9. The true (literature) value for the density of aluminum is 2.70 g/cm3. Two students measure the density of a small

aluminum cylinder in the lab to be 2.45 g/cm3. Calculate the percent error, and explain what this means.

10. A pure gold coin has a diameter of 2.22 cm and is 2.40 mm thick. The density of gold is 19.32 g/cm3. If the price of

gold is $1800.00 per ounce (1 ounce = 28.35 g), how much money is the coin worth?

11. The concentration or strength of an acid solution is often express as pH. The definition of pH is:

pH = - log (H+ concentration)

a. If the H+ concentration in a sample of acid rain is 1.5 x 10-4 , what is the pH? ___________

b. If the pH of swimming pool water is 8.4, what is the [H+] and [OH-]? ____________

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TOPIC 2: MATTER AND ENERGY

• Be able to classify matter into categories. Know the definitions/difference between the terms substance,

element, compound, mixture, solution, homogeneous and heterogeneous.

• Differentiate and give examples of physical properties vs chemical properties of a substance. • Be familiar with energy units: Joule, calorie, and Calorie.

• Know the definition of specific heat capacity (Cp)

• Solve energy problems using the heat transfer equation.

PROBLEMS: 1. Classify each type of matter by writing all the letters that apply to it in the blank:

S = substance Ho = homogeneous mixture

E = element Ht = heterogeneous mixture

C = compound Sl = solution

air ________________________ sea water ________________________

mercury _____________________ brass ________________________

pure distilled water ______________ pizza ________________________

oxygen gas (O2) ________________ methane ________________________

glucose _______________________ zinc ________________________

pure table salt (NaCl) _________________________ gasoline __________________

2. You are given a test tube containing an unknown liquid. Name four physical properties of this liquid you could

measure. Name two chemical properties. Also, what equipment could you use to measure these properties?

3. A candy bar label says that it contains 450 Calories. How many Joules of energy is this?

4. A Styrofoam cup containing 50.0 g of water is placed in a microwave oven and heated for 30 seconds. The

temperature rises from 25.0 oC to 58.0 oC. How much heat (J) did the water absorb?

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TOPIC THREE: ATOMS, IONS AND CHEMICAL FORMULAS

• Memorize the names, formulas and charges of common ions (see separate sheet)

• Be able to name the three basic sub-atomic particles, their mass, charge and general location within

the atom. • Know the difference between an atom and an ion.

• Given the name of an ionic compound, write its chemical formula (from memory).

• Given the chemical formula of an ionic compound, write its correct name.

• Know the meaning of the term isotope. Given the symbol of an isotope, identify its particles.

PROBLEMS 1. Fill in the blanks:

SYMBOL

# Protons

# Electrons

# Neutrons

Na+

_________

__________

__________

Cl-

_________

__________

__________

Iron-56

_________

__________

__________

Fe3+

_________

__________

__________

S2-

_________

__________

__________

Chlorine-37

_________

__________

__________

2. Write the correct chemical formula:

potassium chloride ______________ sodium hypochlorite _____________

magnesium bromide

______________

potassium sulfate

_____________

iron (III) oxide

______________

sulfur (VI) oxide

_____________

barium phosphate

______________

sodium nitrate

_____________

potassium carbonate

______________

copper (II) hydroxide

_____________

potassium permanganate

______________

sodium oxide

_____________

ammonium phosphate

______________

silver carbonate

_____________

tin (IV) bromide

______________

chromium (VI) oxide

_____________

3. Write the correct names of the following compounds:

MgCO3 __________________________________________

CuCl __________________________________________

Sc(NO3)3 __________________________________________

RbO __________________________________________

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NH4NO3 __________________________________________

ZnCl2 ___________________________________________

Ag3PO4

Li2CO3 ___________________________________________

Ba(OH)2 ___________________________________________

Al2(SO4)3 ___________________________________________

KClO3 ___________________________________________

ZnCrO4 ___________________________________________

4. Write isotopic notation for these isotopes:

a. carbon-14 _____________ c. magnesium-25 _______________

b. uranium-235 ___________ d. iron-56 _______________

5. A certain element exists as three different isotopes, with the masses and percentages shown here:

Mass 64 49.0 %

Mass 66 27.8 %

Mass 68 23.0 %

Calculate the average atomic mass of this element, and identify it with its symbol from the periodic table.

TOPIC 4. CHEMICAL EQUATIONS

• Be able to write and balance and classify chemical equations.

BALANCE THE FOLLOWING EQUATIONS

1. C2H2 (g) + O2 (g) CO2 (g) + H2O (g)

2. BaCl2 (aq) + K3PO4 (aq) Ba3(PO4)2 (s) + KCl

3. Al (s) + Cl2(g) AlCl3 (s)

4. K (s) + H2O (l) H2 (g) + KOH (aq)

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5. Fe2O3 (s) + Na (s) Fe (s) + Na2O (s)

6.

NaClO3 (s)

O2 (g)

+

NaCl (s)

7..

H2O2 (aq)

O2 (g)

+

H2O (l)

8. Al(s) + ZnCl2(aq) Zn(s) + AlCl3(aq)

9. . K (s) + H2O (l) KOH (aq) + H2 (g)

10. CaCl2(aq) + Na3PO4(aq) Ca3(PO4)2(s) + NaCl(aq)

11. C2H2 (g) + O2 (g) CO2 (g) + H2O (g)

12. Na (s) + C (s) + O2 (g) Na2CO3 (s)

13. P + O2(g) P2O5

14. C2H6O + O2(g) CO2 + H2O

15. AgNO3 + Na2SO4 NaNO3 + Ag2SO4

2. Write balanced equations for these reactions. (Hint: Make sure you write correct formulas first, then worry about

the coefficients!!).

a. propane gas burns in an outdoor barbecue grill.

b. solid silver oxide decomposes when heated to form solid silver and oxygen gas.

c. a TUMS tablet containing solid calcium hydroxide reacts with hydrochloric acid in a person’s stomach to produce

water and aqueous calcium chloride.

d. Acid rain containing aqueous sulfuric acid reacts with the marble (calcium carbonate) carvings on the walls of a

cathedral to produce carbon dioxide, water, and solid calcium sulfate.

e. sodium metal reacts vigorously with water to produce hydrogen gas and aqueous sodium hydroxide.

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f. In the space shuttle, carbon dioxide from the astronaut’s breathing is filtered thru a filter containing solid lithium

peroxide, and the products are solid lithium carbonate and oxygen gas.

g. Aqueous solutions of silver nitrate and solid sodium chloride are mixed. A white precipitate forms. (In your

equation, indicate which product is the precipitate).

h. Aqueous solutions of barium nitrate and ammonium sulfate are mixed. A white precipitate forms. (Indicate which

product is the precipitate).

TOPIC 5: THE MOLE CONCEPT AND CHEMICAL FORMULAS

• Be familiar with the concept of a mole as the fundamental “counting unit” of chemistry: -- one mole of a substance contains 6.02 x 1023 particles of that substance -- one mole of a substance has a definite mass called its molar mass

• Be able to interconvert between grams, moles and atoms of a given substance

• Be able to calculate the percent composition of a substance

• Be able to calculate the empirical formula of a substance PROBLEMS

1. Convert grams of substance to moles.

a. 222 g Cu metal ______________ b. 500 g of water______________

c. 65.7 g of glucose d. 25.O g of AgNO3 ______________

e. 75.0 g of (NH4)2CO3 ______________ f. 3.2 x 10-3 g of Fe2O3 ______________ 2. Convert moles to grams.

a. 1.50 x 10-3 moles NaOH ___________________

b. 2.50 moles NH3 ___________________

c. 0.346 moles of CuSO4 ___________________ 3. A pure gold coin has a mass of 15.00 grams. How many gold atoms are there in the coin?

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4. What is the percent composition of CuSO4? (In other words, what percentage of this substance, by mass, is due to

copper, sulfur, and oxygen, respectively?)

5. What mass (g) of aluminum oxide (Al203) will contain 50.0 g of aluminum? How many moles of aluminum oxide?

EMPIRICAL AND MOLECULAR FORMULAS

6. Chlorofluorocarbons, or “CFCs” are now banned because they can degrade the ozone layer in the atmosphere. One

such chemical is called freon. A sample of freon consists of 5.70 grams of fluorine, 10.65 grams of chlorine, and 1.79

grams of carbon. Calculate the empirical formula of freon.

7. Nicotine is the poisonous compound found in tobacco leaves. The nicotine molecule consists of

74 % carbon, 8.65 % H, and 17.35 % nitrogen. Determine the empirical formula.

8. A substance used in developing black-and-white photo film has a molar mass of 174 g/mole. It consists of 26.4 %

sodium, 36.9 % sulfur, and 36.7 % oxygen. Determine both the empirical and the molecular formula.

9. A hydrate is an ionic compound that has a certain number of water molecules bonded inside the crystal. For

example, copper sulfate pentahydrate has the formula CuSO4 * 5 H2O, indicating that there are five water molecules for

every formula unit of CuSO4, (or 5 moles of H2O per mole of CuSO4. Heating a hydrate compound drives off the water,

leaving the anyhydrous (“without water”) compound.

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10. Strontium hydroxide exists as a hydrate having the formula Sr(OH)2 * X H2O, where “X” is a small whole number.

Suppose 10.00 grams of this hydrate is heated to drive off the water; the resulting anhydrous compound has a mass of

4.58 grams. Determine the value of “X” and write the formula for the hydrate.

TOPIC 6: BASIC STOICHIOMETRY

• Be able to solve basic mass-mass and mass-volume stoichiometry problems

PROBLEMS:

1. The emergency oxygen system in some jetliners is based upon a decomposition reaction of sodium chlorate

(NaClO3):

2 NaClO3 3 O2 (g) + 2 NaCl (s)

As the reaction equation shows, when a canister of sodium chlorate is heated, it decomposes to form oxygen gas and

sodium chloride. If each passenger requires 450 grams of oxygen gas in an emergency, how many grams of sodium

chlorate must be provided for each passenger?

2. Aluminum metal reacts with aqueous zinc nitrate to form zinc metal and aluminum nitrate.

The equation is 2 Al (s) + 3 Zn(NO3)2 (aq) 3 Zn (s) + 2 Al(NO3)3(aq)

a. Starting with 7.50 grams of aluminum metal, how many grams of zinc can be formed?

b. Starting with this same amount of aluminum, how many grams of zinc nitrate will be needed?

3. Referring to problem #2 above, if you started with 7.50 grams of aluminum and 7.90 grams of zinc nitrate, how much

zinc metal would be produced?

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4. The compound called trinitrotoluene, or “TNT”, is an explosive. When TNT detonates, it forms many different

products, as shown in this balanced equation:

2 C7H5N3O6 12 CO (g) + 5 H2 (g) + 3 N2 (g) + 2 C (s)

TNT

a. If a block of TNT with a mass of 5.00 x 102 g explodes, how many grams of nitrogen gas will be formed?

b. If there were 4.00 x 102 g of carbon dioxide available, would all of the TNT be used up? Why or why not?

The next three questions refer to the combustion reaction of propane gas (C3H8) shown here:

C3H8 (g) + 5 O2 (g) 3 CO2 (g) + 4 H2O (g) + 150 kJ

3. How many grams of water will be formed by burning 75.0 g of propane?

4. What volume of carbon dioxide, measured at standard temperature and pressure (STP) will also be formed when this

amount (75.0 g) of propane is burned? (Recall: 1 mole of any gas at STP has a volume of 22.4 Liters).

5. How much heat energy (Joules) will be given off when this amount of propane is burned? (Hint: the equation shows

you how much heat is given off when 1 mole of propane is burned).

TOPIC 7: ELECTRON STRUCTURE OF THE ATOM AND ORGANIZATION OF THE

PERIODIC TABLE OF THE ELEMENTS

• Given an element between H and Kr, be able to write its complete electron configuration.

• Be able to state the basic principles by which the modern Periodic Table of the Elements is organized.

PROBLEMS

1. Identify the element:

a. Electron configuration is 1s22s22p5

b. Electron configuration is 1s22s22p63s23p64s23d6

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c. Electron configuration is [Ar] 4s2

d. Electron configuration ends in --4p4

2. Write the electron configuration for these elements:

a. sodium ________________________

b. zinc ________________________

c. neon ________________________ d.

fluorine ________________________ e.

nitrogen ________________________

3. State how many unpaired electrons these atoms have:

a. lithium _______ c. carbon _______

b. nitrogen _______ d. zinc _______

4. State how many valence electrons these atoms have:

a. carbon _______ c. phosphorus ________

b. sulfur _______ d. krypton ________

5. Organization of the Periodic Table

a. In what order are the elements arranged? ____________________________________

b. What is significant about the electron configuration of two elements that are in the same group (vertical

column) of the Table?

c. What can you say about the chemical properties of elements in the same Group?

d. List four alkali metals alkaline earth metals halogens

TOPIC 8: CONCENTRATION OF SOLUTIONS (Molarity)

• Know the definition of molarity and be able to calculate molarity of solutions.

PROBLEMS:

1. 50.0 g of NaCl are dissolved in water to make 250. mL of solution.

a. Calculate the molarity.

b. If the same mass of NaCl is dissolved in 250. g of water (remember the density of water = 1g/ cm3; 1 cm3 = 1 mL),

what is the molality?

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2. What mass of silver nitrate do you need to make 250. mL of a 0.0150 M solution?

3. What volume (mL) of 1.50 M CuSO4 solution will contain 16.5 g of CuSO4?

4. You have 250 cm3 of a silver nitrate solution that is 2.00 M concentration. You dilute the solution until the total

volume is now 1000 cm3. What is the new concentration? TOPIC 9: THE BEHAVIOR OF GASES

1. A 8.00 L fire extinguisher contains nitrogen gas at a pressure of 1.25 x 105 kPa and temperature of 35.0 oC. What

volume will this gas occupy as standard temperature and pressure (STP)?

2. A 50.0 cm3 sample of gas has a pressure of 98.5 kPa at 25.0 oC. How many moles of gas does this sample contain?

3. Several years ago, a frozen mummy was found in the Italian alps. This ancient man was carrying an axe made of

copper. Early man made copper by heating copper oxide ore (CuO) with charcoal (carbon) in campfires: 2 CuO

+ C 2 Cu (s) + CO2 (g) What volume of carbon dioxide gas, measured at STP, will be produced from the reaction of

530 g of copper oxide ore?

4. A tank contains a mixture of four gases. The amount of each gas is shown below. The total pressure of the mixture

is 2400 pascals. What is the partial pressure of each gas?

Helium = 2 moles

Oxygen = 1.5 moles

Ammonia = 3.0 moles

Carbon dioxide = 1.5 moles

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5. Calculate the density of propane gas (C3H8) at STP.

TOPIC 10: STRUCTURE AND SHAPE OF MOLECULES

For each molecule, draw the correct Lewis electron dot structure. Then use the VSEPR concept to predict the shape of

the molecule: bent, triangular pyramid, triangular planar, tetrahedron, or linear.

Molecule Lewis Structure Shape (Geometry/ Name)

H2O

NH3

CH2O

SbF6

HCN

SiCl4

O3

PCl5

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TOPIC 11: ACIDS AND BASES

1. Write two chemical equations, illustrating the Arrhenius definition of an acid and a base.

2. What is the Brønsted-Lowry vs. Lewis definition of an acid and a base?

3. Label each species as A (acid), B (base), CA (conjugate acid), or CB (conjugate base).

A. NH3 (g) + H2O (l) NH4+ (aq) + OH-(aq)

B. CH3OH (aq) + NH2- (aq) CH3O- (aq) + NH3 (g)

C. OH- (aq) + HSO4-(aq) SO4

2- (aq) + H2O (l) 4. Write correct chemical formulas for the following

a. conjugate acid of water _________________

b. conjugate acid of the chloride ion _________________

c. conjugate base of acetic acid _________________

d. two conjugate bases of sulfuric acid ______________________

TOPIC 12: THERMODYNAMICS

1. A change in temperature from 10 °C to 20 °C is found to double the rate of a given chemical reaction. How did this

change affect the reacting molecules?

(A) It doubled their average velocity.

(B) It doubled their average energy.

(C) It doubled the number of collisions per second.

(D) It doubled the proportion of molecules possessing at least the minimum energy required for the reaction.

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2. The rate equation for a chemical reaction is determined by

(A) theoretical calculations.

(B) measuring reaction rate as a function of concentration of reacting species.

(C) determining the equilibrium constant for the reaction.

(D) measuring reaction rates as a function of temperature.

3. The value of the rate constant of a reaction can generally be expected to

(A) be independent of temperature.

(B) increase with increasing temperature.

(C) decrease with increasing temperature.

(D) decrease with increasing temperature only if the reaction is

exothermic.

4. Which line in the diagram represents the activation energy for a forward

reaction? (A) (B) (C) (D)

5. The rate law for the reaction A + B → C + D is first order in [A] and second order in [B]. If [A] is halved and [B] is

doubled, the rate of the reaction will

(A) remain the same.

(B) be increased by a factor of 2.

(C) be increased by a factor of 4.

(D) be increased by a factor of 8.

6. In a chemical reaction involving the formation of an intermediate activated complex, which step must always be

exothermic?

(A) Reactants → products (B) Products → reactants

(C) Reactants → activated complex

(D) Products → activated complex

(E) Activated complex → products

7. The addition of a catalyst in a chemical reaction

(A) increases the concentration of products at equilibrium.

(B) increases the fraction of reactant molecules with a given kinetic energy.

(C) provides an alternate path with a different activation energy.

(D) lowers the enthalpy change in the overall reaction.

8. A catalyst will

(A) alter the pathway (mechanism) of a chemical reaction.

(B) increase ΔH for the reaction.

(C) decrease ΔH for the reaction.

(D)decrease Ea for the forward reaction only

9. The following mechanism has been proposed for the formation of ethylbenzene:

For the mechanism provided, which substance serves as the

catalyst?

(A) AlBr3 (B) AlBr4–

(C) CH3CH2+ (D) C6H6CH2CH3

+

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11. The table presents data for the reaction:

12. What is the rate law for this reaction?

(A) rate = k1 [H2 ] [NO] (B) rate = k1 [H2 ]2 [NO]2

(C) rate = k1 [H2]2 [NO] (D) rate = k1 [H2] [NO]2

13. In which reaction will an increase in total pressure at constant temperature favor formation of the products?

14. The equilibrium constant for the gaseous reaction C + D E + 2F is 3.0 at 50 °C. In a 2.0 L flask at 50 °C

are placed 1.0 mol of C, 1.0 mol of D, 1.0 mol of E, and 3.0 mol of F. Initially, the reaction will: (A) proceed at equal rates in both directions. (B) proceed more rapidly to form E and F. (C) proceed more rapidly to form C and D. (D) not occur in either direction.

15. Consider this reaction.

The conditions of temperature and pressure that favor the formation of CO2 are: (A) high T and high P. (C) low T and high P. (B) high T and low P. (D) low T and low P.

16. For the reaction

2SO2(g) + O2(g) 2SO3(g) ΔH = –198 kJ

carried out at constant volume, the concentration of O2 at equilibrium will increase if (A) SO2 is added to the system. (B) SO3 is added to the system. (C) the temperature of the system is lowered.

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(D) an inert gas is added to the system.

17. Which factor would cause a change in the equilibrium constant, Kc, for this reaction?

2NOCl(g) 2NO(g) + Cl2(g) (A) adding NO(g) (B) decreasing the volume of the reaction vessel (C) cooling the system (D) adding an inert gas

18. A 1.20-L flask contains an equilibrium mixture of 0.0168 mol of N2, 0.2064 mol of H2, and 0.0143 mol of

NH3. Calculate the equilibrium constant, Kc for the reaction

N2(g) + 3H2(g) 2NH3(g)

(A) 1.38 (B) 1.99(C) 4.12 (D) 4.96 19. Given the exothermic reaction:

N2(g) + 3H2(g) 2NH3(g) ΔH = –92.1 kJ

At 400 K, the equilibrium constant is 0.53. At 800 K, what is the value of the equilibrium constant; what does that mean?