Chemistry 30S – Exam Review

Unit #1-Physical Properties of Matter

  1. Complete the following table.

PhysicalState / Density / Compressibility / Diffusion / Intermolecular Forces
Solid
Liquid
Gas
  1. What is the Kinetic Molecular Theory?
  2. What is evaporation and condensation? Use the following terms in your explanations: intermolecular forces, random motion, dynamic equilibrium, and atmospheric pressure. Draw a diagram.
  3. Refer to phase change diagram on Physical properties test, where is the triple point?

Chemistry 30S – Exam Review – Answer Key

Unit #1-Physical Properties of Matter

1.

PhysicalState / Density / Compressibility / Diffusion / Intermolecular Forces
Solid / High density / Can’t be compressed / Not able to diffuse / Strong
Liquid / Moderate density / Very low to no compressibility / Not able to diffuse / Moderate
Gas / Low density / High compressibility / Easily diffused / Weak
  1. The Kinetic Molecular Theory describes the motion of particles in matter and the forces of attraction between them. As a substance changes from a solid to a liquid to a gas, the speed of particles changes and so do the forces of attractions between each particle in the substance.
  2. Refer to your test!

Chemistry 30S – Exam Review

Unit #2-Gases and the Atmosphere

  1. What gases occur naturally in our atmosphere and how have they changed over time?
  2. Make the following conversions:

a)2.3 atmospheres = ______kilopascals

b)680 mm of Hg = ______atmospheres

c)110 kPa = ______psi

  1. The volume of a gas at 155.0 kPa changes from 22.0 L to 10.0 L. What is the new pressure if the temperature remains constant?
  2. Exactly 10.0 L of O2 at -25oC is heated to 100.0 oC. What is the new volume if the pressure is kept constant?
  3. A gas at a pressure of 4.95 atm and a temperature of 25 oC occupies a volume of 5.2 L. When the gas is heated to 100.0 oC the volume increases to 7.00 L. What is the new volume?
  4. A sample of O2 with an initial temperature of 50.0 oC and a volume of 105 L is cooled to -25oC. The new pressure is 105.4 kPa and the new volume is 55.0 L. What was the initial pressure of the sample?.

Chemistry 30S – Exam Review-Answer Key

Unit #2-Gases and the Atmosphere

  1. Refer to the handout at the beginning of the gases unit.
  2. a) 232.99

b)0.89

c)15.96

  1. 341 kPa
  2. 15.0 L
  3. 4.60 atm
  4. 71.9 kPa

Chemistry 30S – Exam Review

Unit #3-Chemical Reactions

  1. There are five naturally occurring isotopes of the element zinc. The relative abundance and mass of each are as follows. Calculate the average atomic mass of zinc.

Zn = 48.89%, 63.929 amu

Zn = 27.81%, 65.926 amu

Zn = 4.11%, 66.927 amu

Zn = 18.57%, 67.925 amu

Zn = 0.62%, 69.925 amu

  1. Write the formulas for the following:

a)magnesium nitride

b)copper (I) sulfate

  1. Name the following compounds:

a)Ca3P2

b)Al(NO3)3

  1. Complete the following reactions, balance, and state the type of reaction it is.

a)CaCO3 + HCl →

b)Co + O2 →

c)FeO + Al →

d)NH3 →

  1. Balance the following chemical equations:

a)H2 + O2 → H2O

b)AgNO3 + Zn → Zn(NO3)2 + Ag

c)Al2(SO4)3 + BaCl2 → AlCl3 + BaSO4

  1. What is the molar mass of Li3PO4?
  2. How many molecules are present in a mole of BaCl2?
  3. What is the mass of 3.20 moles of Zn(NO3)2?
  4. A piece of marble (CaCO3) contains 8.74 x 1023 molecules. How many moles is this?
  5. A room with a volume of 4000 L contains how many moles of air at STP?
  6. How many moles of HCl are needed to react with 2.3 moles of Zn?

2 HCl + Zn → ZnCl2 + H2

13. Determine the mass of sodium hydroxide produced when 0.25 g of sodium reacts with water according to the following equation:

2 Na + 2 H2O → 2 NaOH + H2

14. How many liters of oxygen are necessary for the combustion of 340 g of ethanol (C2H5OH) assuming that the reaction occurs at STP? The balanced chemical equation is: C2H5OH + 3 O2 → 2 CO2 + 3 H2O

15. Identify the limiting reactant when 10.0 g of H2O reacts with 4.5 g of Na to produce NaOH and H2. How much is in excess?

Chemistry 30S – Exam Review-Answer Key

Unit #3-Chemical Reactions

  1. 65.37 amu
  2. a) Mg3N2

b) Cu2SO4

4. a) Calcium phosphide

b) Aluminum nitrate

5. a) CaCO3 + 2 HCl → CaCl2 + H2CO3 (DD)

b) 2 Co + O2 → 2 CoO (S)

c) 3 FeO + 2 Al → Al2O3 + 3 Fe (SD)

d) 2 NH3 → N2 + 3 H2 (D)

6. a) 2,1,2

b) 2,1,1,2

c) 1,3,2,3

7. 115.8 g

8. 6.02 x 1023 molecules

9. 606.1 g

10. 1.45 moles

11. 178.6 moles

12. 4.6 moles

13. 0.43 g

14. 496.0 L

15. Na is the limiting reactant. 6.5 g of H2O will be left over.

Chemistry 30S – Exam Review

Unit #4-Solutions

  1. Define: homogeneous, supersaturated, soluble, molarity.
  2. Give an example of each type of solution. (There are 9)
  3. Why do oil and water not mix?
  4. Be able to read and answer questions about a solubility curve.
  5. Explain how a change in temperature affects the solubility of gases.
  6. What is the molarity of a NaCl solution if 9.0 g of NaCl is dissolved in water to make 0.50 L of solution?
  7. How many moles of bromine (Br2) are needed to prepare 0.500 L of a 0.0100 mol/L solution of bromine in water?
  8. Explain how you would prepare a 0.250 M solution of potassium chromate if you had a 500 mL volumetric flask.

Chemistry 30S – Exam Review-Answer Key

Unit #4-Solutions

  1. Homogeneous – a solution is homogeneous. The solute is evenly distributed through the solvent.

Supersaturated – a solution that contains a greater amount of solute than can possibly be dissolved at that temperature. This is achieved by increasing the temperature, saturating it again, and then slowly and carefully lowering the temperature again. It is an unstable solution.

Soluble – When a solute can dissolve in a solvent.

Molarity – The number of moles of solute that can dissolve in 1 liter of solution.

  1. Refer to handout from the powerpoint presentation.
  2. Water is polar and oil is nonpolar. “Like dissolves like” means that only substances which have the same bonding type will dissolve in each other. Therefore water and oil will not mix.
  3. Find a set of questions from class and try them again.
  4. Gases are unlike solids when they dissolve in liquids. Gases generally dissolve less in liquids when the temperature of the solution is increased.
  5. 0.3 mol/L
  6. 0.005 moles
  7. Mass out 24.3 grams of K2CrO4. Add to a 500 mL volumetric flask. Add some water, swirl to dissolve the K2CrO4, then add enough water until it reaches the 500 mL mark and swirl again.

Chemistry 30S – Exam Review

Unit #5-Organic Chemistry

  1. Create a foldable for the naming rules of alkanes, alkenes, and alkynes.