GHS Honors Chemistry June 2014 Final Exam Part II Review
The following questions are an overview of the types of questions that you will be required to answer on your final exam. The questions on your exam will be similar to the ones on this review. Since the questions are distributed in advance, there will be no answer key provided. You may work with your fellow students to answer these questions as needed. For the final exam, you will answer 6 randomly selected questions based on those presented below for 5 points each, totaling 30 points.
1. Describe or draw a concept map that illustrates the different classifications of matter. Draw diagrams to show the differences between pure substances and mixtures on a particle basis.
2. Explain how the atoms of one element differ from another. In what way are isotopes of the same element different? Does this affect properties of the element? What makes an isotope radioactive? Describe the nature of radioactive decay and why elements decay.
3. Given these reactants: potassium sulfate + barium nitrate ?? complete the following: a. Complete the word equation (name the products that will form) b. Write the symbolic equation with the correct formulas. c. Balance the equation and record in writing the steps you used in your approach to balancing the equation. d. State the reaction type and what indicators you used to arrive at your decision. e. Identify the precipitate.
4. Distinguish between polar covalent, nonpolar covalent and ionic bonds. Give an example of a compound with each bond type to help explain your answer. Identify and explain why the
shape of CCl4 and PF3 are different. What factors create these shapes?
5. Explain the importance or significance of electron configuration with respect to compound formation, reactivity, and periodic trends.
6. Given your knowledge of gas behavior and the kinetic molecular theory:
a. Sketch the gas particles in a balloon submerged in both hot water and cold water.
b. Using the kinetic molecular theory explain how decreasing the volume of a gas, at constant temperature, causes the gas pressure to change.
c. What volume will 2.00g of NO2 occupy at a pressure of 1.00 atm and a temperature of 50°C.
7. Define the term solute, solvent and aqueous solution. Discuss at least 3 factors that affect solubility of solids in water and include specific examples in your discussion. Explain on a particle basis how the addition of a solute affects boiling point and freezing point. Show how 8.0 g of magnesium chloride and 8.0 g of glucose would affect either the freezing or boiling point of 0.50 kg of water.
8. Compare and contrast Molarity and molality. Describe how you would prepare each of the following: 0.33 M solution of potassium chloride and 0.33 m solution of potassium chloride. o Calculate the freezing point of water using the concentration above. The Kf is 1.86 C/m.
9. Explain how the elements of the Periodic Table are arranged. Describe 5 ways the Periodic Table has been useful to you in chemistry class this year. Given the elements Na and F, state the differences in atomic radius, electronegativity, ionization energy and metallic character. Choose any one of the trends and explain the reason why it increases or decreases across a period and down a group.
10. Explain how ions form and show examples. Use diagrams if needed. Given the calcium ion and the phosphide ion, write the chemical formula for the compound produced by these 2 ions, explaining the steps you took to arrive at the formula. If calcium is changed to lithium, how is the formula affected?
11. Describe the effect of a catalyst on the rate of reaction. Include a labeled potential energy diagram showing an exothermic reaction and the effect of the catalyst on the reaction pathway. Choose 2 of the following: temperature, concentration of reactant, stirring, or surface area and describe the effect on reaction rate.
12. Describe the 3 factors that affect the spontaneity of a reaction. Predict whether this reaction o would be spontaneous at 45 C : 2 NH3(g) + Q N 2(g) + 3 H2(g) Explain your reasoning.
13. The value of H for a reaction is negative. Explain the difference in energy between products and reactants for this reaction. For the combustion of methane, write and balance the reaction and determine the enthalpy by standard heats of formation. Which would have a higher energy, products or reactants? Under what conditions does Hess’s Law have to be used to determine enthalpy of an overall reaction.
14. Joe and Mary conducted an experiment to determine the specific heats of a two materials to determine which is better at keeping drinks hot or cold. They constructed a coffee cup calorimeter and collected data to determine the specific heats of the materials. Support your answer with data and a written response of at least two sentences.
Test Mass of Initial H20 Final H20 Mass of Initial Temp of
H20 Temperatur Temperatur sample sample Coffee e e Cup Material
Sample A 100.0 g 20.0°C 23.0 C 20.0 g 72.1 °C
Sample B 100.0 g 20.0 °C 21.8 C 20.0 g 96.0 C
15. What is the importance of the Rate Law? Write a clear definition for a 1st order and 2nd order reaction. Then, given the initial rate data below, write the rate order of A and B and determine the value of k for the following reaction:
H2(g) + Cl2(g) 2 HCl(g) + Q
Experiment H2(g) mol/L Cl2(g) mol/L Rate mol/L sec
1 0.0010 0.0040 1.3 X 10-5
2 0.0020 0.0040 5.2 x10-5
3 0.0040 0.0080 4.16 x 10-5
4 0.0040 0.0160 8.32 x 10-5
16. Explain the concept of chemical equilibrium. Identify three factors that disrupt a system that is at chemical equilibrium according to Le Chatelier’s principle. State 2 ways to shift the direction in the equilibrium to produce more product for the reaction below: N2(g) + 3 H2(g) 2 NH3(g) + Q
o 17. At 25 C, 0.02 mol N2O and 0.60 mol O2 are placed in a 1.0 L container where the following equilibrium is established:
2 N2O(g) + 3 O2(g) 4 NO2(g)
At equilibrium, the NO2concentration was 0.020 M. What are the equilibrium concentrations for the reactants and products and what is the value of Keq for this reaction. 18. In the laboratory, students wanted to mimic the inflation of an airbag by mixing sodium bicarbonate and acetic acid in a zip lock bag. Assuming you could conduct this experiment to fill up a 4 liter zip lock bag, determine the mass of the baking soda and the acetic acid needed to fill the bag. The reaction is below:
NaHCO3(s) + CH3COOH(l) H2O(l) + CO2(g) + NaC2 H3O2
19. Compare and contrast the properties and characteristics of acids and bases. What tests would you recommend for determining the level of acidity or basicity of an unknown material? Which acid-base theory do you believe best describes acids and bases? Why?