Chemistry Honors Practice test on Acids, Base and Chemical Equilibrium

1. A base can:

a)React w/ zinc to produce H2 gas b) A and D only c) A and E only

d)Donate H+ ions e)Accept H+ ions

2. A neutralization reaction produces:

a)water and hydroxide ions b)water and hydronium ions

c)an ionic salt and water d)A and C e)B and C

3. A solution labeled .400 M barium hydroxide contains what molar concentration of OH- ions?

a) .100 M b) .200 M c) .400 M d) .600 M e) .800 M

4. What volume of .75 M HNO3 is necessary to react exactly with 3.7 g of Ca(OH)2?

a)2.0 x 102 mL b)2.5 x 102 ml c)1.3 x102 mL d)8.0 x102 mL e)1.6 x 102 mL

5. For the reaction

CO(g) + Cl2(g) <--COCl2(g)

at a particular temperature, K = 5.1 x 109 when all concentrations are expressed in moles/liter. Pure COCl2 is added to a 1-liter flask. At equilibrium it is found that 0.25 moles of COCl2 remain. What is the equilibrium concentration of CO?

a) 0.75 M b) 1.4 x 10- 5 M c) 7.0 x 10- 6 M d) 4.9 x 10- 11 M e) none of these

6. Consider the following system at equilibrium:

N2(g) + 3H2(g) ---2NH3(g) + 92.94 kJ

Which of the following changes will shift the equilibrium to the right?

1. increasing the temperature 2. decreasing the temperature

3. increasing the volume 4. decreasing the volume

5. removing some NH3 6. adding some NH3

7. removing some N2 8. adding some N2

a) 1,4,6,7 -b) 2,3,5,8 -c) 1,6,8 -d) 1,3,5,7 -e) 2,4,5,8

7. For the equilibrium which exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is:a) K = [H+][NO2-] / [HNO2] b) K = [H+][N][O]2 / [HNO2] c) K = [H+][NO2-] d) K = [H+]2[NO2-] / [HNO2] e) none of these

8.Calculate the [H+] in a solution which shows a pH of 2.30.

a) 2.3 M b) 11.7 M c) 5.0 x 10-3 M d) 2.0 x 10-12 M e) none of these

9. Which of the following indicates the MOST ACIDIC solution?

a)[OH-] = 0.5 M b) [H+] = 0.3 M c) pOH = 5.9 d) pH = 1.2 e) [H+] = 1 x 10-4 M

10.Write formulae/name of two salts one that produces an acidic solution when dissolved in water and other that produces a basic solution.

11. Write an example of an acidic and a basic buffer.

12. How many calories are required to heat 5.0 g of Pyrex glass from 15.0 C to 65.0 C? (Specific heat of Pyrex glass = 0.20 cal/g.C)

A. 5 kcal

B. 50 kcal

C. 500 cal

D. 0.050 kcal

13. Calculate the enthalpy of condensation of 1.00 g of water at 100 C if ∆Hcondensation =

-9.72 kcal/mol

A. 547 cal

B. 540 cal

C.1026 cal

D. None of the above

14. Given the following reactions and ∆H values,

a. 2 N2O(g) --- O2(g) + 2 N2(g) ∆H = -164 kJ

b. 2NH3(g) + 3N2O (g) ---- 4 N2(g) + 3H2O(l) ∆H= -1012 kJ

∆H for 4NH3(g) + 3O2(g) ---2N2(g) + 6H2O(l)

  1. 1250kJ
  2. – 1532 kJ
  3. 1000 kJ
  4. – 3064 kJ

15. Use the data below to calculate ∆H for the reaction

N2O4 + CO N2O + CO2

compound / ∆Hof (kJ/mol)
CO(g) / -110
CO2(g) / -393
N2O(g) / 81
N2O4(g) / 9.7

A. –431.7 kJ

B. 431.7 kJ

C. –778 kJ

D. None of the above

16. For the following process, indicate whether the disorder of the system increases, decreases or remains nearly the same

Mg (s) + Cu+2(aq) Mg+2(aq) + Cu(s)

A. increases

B.decreases

C. stays nearly the same

D. None of the above

17) Given the information below, calculate∆ Go for

2SO2(g) + O2(g) 2SO3(g)

∆ Gof : SO2(g) = -300.3, SO3 (g)= -371.1 kJ/mole

A. –600.6 kJ

B. –70.8 kJ

C. –141.6 kJ

D. 0 kJ

Use the energy diagram below to answer questions 18 &19

C

D+E

A+B

Course of reaction

18) In the above diagram, C represents

A. An activated complex

B. A reactive intermediate

C. Reactant

D. Product

19. Does the energy diagram show an endothermic or exothermic reaction? Label reactants, products, Ea and Ea’.

Answers to the test