Question 20. The rates of which reactions are increased when the temperature is raised?
I. PART 1 (7.0 points) Question 1. A student poured 100 mL of water in a bottle and added 40 mL vinegar to
Slowly the shape of the balloon changed, as shown.
The student claims that a chemical change happened when the two substances were mixed. Is the claim made by the student correct?
A. Yes, as a new substance was formed in the form of a gas.
B. Yes, as the mass remains the same throughout the experiment.
C. No, as the formation of bubbles in the mixture shows a physical change.
D. No, as the change in the shape and size of the balloon shows a physical change.
Question 2. Iron(II) sulfide reacts with gaseous hydrogen chloride to produce iron(III) chloride and hydrogen sulfide. How much iron(II) sulfide would be required to react with 1.5 mol HCl?
A. 0.25 mol B. 1.50 mol C. 0.75 mol D. 1.0 mol Question 3. A student wishes to prepare a solution with a final concentration of [Na+] = 0.50 M and a final concentration of [HCO3
–] = 0.10 M by taking some NaOH and some trona (Na2CO3•NaHCO3•2H2O) and diluting with water to a final volume of 1.00 L. How much NaOH and trona are required?
A. 0.05 mol NaOH, 0.15 mol trona B. 0.20 mol NaOH, 0.10 mol trona
C. 0.35 mol NaOH, 0.05 mol trona
D. A solution cannot be prepared with the desired concentrations of Na+ and HCO3 –
using only NaOH and trona.
Question 4. As the concentration of an aqueous solution of sodium chloride increases from 1.0 M to 2.0 M, the values of which properties of the solution decrease?
I. Density II. Freezing point
A. I only B. II only C. Both I and II D. Neither I nor II Question 5. Mixing which 0.1 M aqueous solutions results in formation of a colored precipitate?
A. BaCl2 and CH3COOH B. BaCl2 and Na2CO3 C. CuCl2 and CH3COOH D. CuCl2 and Na2CO3
Question 6. Which of the following solute/solvent pairs best represents the principle of completely dissolved?
A. carbon dioxide in water B. lipids (fats) in water C. potassium iodide in benzene ( C6H6) D. hydrogen chloride in water
Question 7. A reaction A → 2 B was monitored over time. What is the average rate of disappearance of A between t = 0 and t = 10 minutes?
Time of reaction (min)
A. 0.03 M min-1 B. 0.04 M min-1 C. 0.06 M min-1 D. 0.07 M min-1 Question 8. A sample of SO2Cl2 is introduced into a movable piston with the pressure
maintained at 1.00 atm and the temperature at 450 K. The volume increases as the sulfuryl chloride equilibrates according to the following endothermic reaction:
SO2Cl2(g) SO2(g) + Cl2(g) ∆H° > 0
Which changes would decrease the number of moles of SO2Cl2(g) present in the piston at equilibrium? In each case, the pressure is maintained at 1.00 atm.
I. The temperature of the system is increased to 500 K.
II. A sample of Cl2(g) is injected into the piston.
A. I only B. II only C. Both I and II D. Neither I nor II Question 9. When the following reaction is balanced under basic conditions, what is the ratio of the coefficients of Mn(OH)2(s) to MnO42-
(aq)?
Mn(OH)2(s) + MnO4
–(aq) → MnO42- (aq)
A. 3 : 1 B. 1 : 3 C. 1 : 4 D. 1 : 5 Question 10. Which substance is most likely to be soluble in a nonpolar solvent?
A. glucose B. graphite C. lithium fluoride D. sulfur Question 11. A 20.00 mL sample of a Ba(OH)2 solution is titrated with 0.245 M HCl. If 27.15 mL of HCl is required, what is the molarity of the Ba(OH)2 solution?
A. 0.166 M B. 0.180 M C. 0.333 M D. 0.666 M Question 12. What is the mass percent of oxygen in Al2(SO4)3ã18H2O?
A. 9.60 B. 28.8 C. 43.2 D. 72.0
Question 13. Which solid reacts with dilute hydrochloric acid at 25 C to produce a gas that is more dense than air?
Question 14. The rate of formation of O3(g) is 2.0 ì 10–7 molãL–1ãs–1 forthe reaction 3O2(g)→ 2O3(g)
What is the rate of disappearance of O2(g) in molãL–1ãs–1?
A. 1.3 × 10–7 B. 2.0 × 10–7 C. 3.0 × 10–7 D. 4.5 × 10–7 Question 15. Which is the best way to prepare 500 mL of a 2.00 M solution of aqueous H2SO4 from deionized water (M = 18.02, density = 1.00 g mL–1) and concentrated H2SO4 (M = 98.08, density = 1.84 g mL–1)?
A. Weigh 98.1 g concentrated sulfuric acid into a 500-mL beaker, then slowly add deionized water to the beaker, with occasional swirling, until the liquid reaches the 500 mL mark.
B. Weigh 98.1 g concentrated sulfuric acid into a 500-mL volumetric flask, slowly add deionized water to the mark, and mix.
C. Weigh 98.1 g concentrated sulfuric acid into a 100-mL beaker, then slowly pour the H2SO4 into a 500-mL beaker with about 250 mL deionized water in it. Pour this
solution into a 500-mL volumetric flask and fill to the mark with deionized water and mix.
D. Weigh 446.6 g deionized water into a 500-mLvolumetric flask, fill to the mark with concentrated sulfuric acid, and mix.
Question 16. . In the manufacture of paper, sulfur dioxide is used to remove the yellow colour from the wood pulp. Which term can be used to describe sulfur dioxide in this process?
A. a bleach B. a catalyst C. an oxidising agent D. a solvent Question 17. What is the formula of the oxide whose unit cell is shown?
A. Ce7O4 B. CeO C. Ce2O3 D. CeO2
Question 18. Iodide ion is oxidized to hypoiodite ion by permanganate ion in basic solution according to the following unbalanced equation:
I–(aq) + MnO4–(aq) IO–(aq) + MnO2(s)
What is the ratio of hydroxide ions to iodide ions in the balanced equation?
A. 3:1 B. 2:1 C. 1:1 D. 2:3 Question 19. In the carbon monoxide complex Na[V(CO)6], what is the oxidation number of vanadium?
A. -1 B. +3 C. +5 D. +6
Question 20. A lump of element X can be cut by a knife. During its reaction with water, X floats and melts. What is X?
A. calcium B. copper C. magnesium D. potassium Question 21. A student experimented with magnesium ribbon and hydrochloric acid.
• The student placed a piece of solid magnesium ribbon in a test tube containing hydrochloric acid solution.
• The student observed that vigorous bubbling occurred.
• The student collected some of the gas generated by the bubbles in a test tube.
• The student tested the gas produced with a burning wood splint, which ignited quickly with a popping sound.
What can the student conclude about the experiment?
A. A chemical reaction occurred because new atoms were created.
B. A chemical reaction occurred because a new substance was formed.
C. The popping sound provided evidence that the acid changed physical states.
D. The popping sound provided evidence that the magnesium atoms were destroyed.
Question 22. Of the following compounds, which are not likely to increase in solubility as the temperature of the solution increases?
1. CH4 2. NaBr 3. CO2 4. Glucose, C6H12O6 5. CuSO4
A. 2 and 3 B. 1 and 3 C. 1 and 4 D. 5 only Question 23. An equilibrium is established between substances W, X, Y, and Z.
W + X Y + Z
How would the conditions of equilibrium be affected by decreasing the concentration of substance W?
A. Substances X and Y would react to replace substance W, and the position of equilibrium would shift to the right.
B. Substances Y and Z would react to replace substance W, and the position of equilibrium would shift to the left.
C. This would increase pressure, causing only substance Y to replace substance W and shifting the equilibrium to the right.
D. This would decrease temperature, causing only substance Z to replace substance W and shifting the equilibrium to the left
Question 24. A student describes a liquid as feeling slippery. The student places red litmus paper into the liquid, and the paper turns blue. What can the student conclude from these observations?
A. The substance is likely a nonmetal. B. The substance is likely a metal.
C. The substance is likely a base. D. The substance is likely an acid.
Question 25. An acid-base titration is represented by the chemical equation below.
CsOH (aq) + HBr (aq) → CsBr (aq) + H2O (l)
In the titration, 15.0 mL of CsOH solution is neutralized by 38.2 mL of 0.250 M HBr solution. What is the molarity of the CsOH solution?
A. 0.0982M B. 0.637M C. 1.36M D. 10.2
Question 26. What type of solution is formed when solid sodium hydroxide (NaOH) is dissolved in water?