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Chemistry 100
Chapters 14-16 review
1. A sodium hydroxide solution has a pH of 10.40. What is the [H+], [OH-], and pOH?
2. If 33.2 mL of an aqueous solution of HCl requires 52 mL of 0.74 M NaOH to reach the end
point, what is the molarity of the HCl solution?
3. If 54 mL of an aqueous solution of H3PO4 requires 34 mL of 0.83 M NaOH to reach the
end point, what is the molarity of the H3PO4 solution?
4. Show the acid, base, conjugate acid and conjugate base in following reactions:
a) H2SO4 + Mg(OH)2 → MgSO4 + 2H2O
b) HNO3 + NH3 → NH4+ + NO3-
5. Write the formula for the conjugate base of each acid.
a) H2SO4
b) H3BO3
c) HI
d) H3O+
e) NH4+
f) HPO42-
Dr. Behrang Madani
Chemistry 100
IVC
6. Write the formula for the conjugate acid of each base.
a) HSO4-
b) NH3
c) H2O
d) Br-
e) PO33-
f) HPO42-
7. What is the molarity of a solution made by dissolving 9.1 g of H3PO4 in enough water to
make 22.3 L of solution? Assume that H3PO4 ionizes completely in water to H+ and PO43ions. What is the pH of the solution? Find the concentration of OH-?
8. Calculate pH of a buffer solution prepared from 0.1 mole of formic acid (HCOOH) and
0.02 mole of sodium formate (HCOONa) diluted to 1L. (pKa of formic acid is 3.75)
9. Write the equilibrium expression for the follwoing equations:
a) H2(g) + Br2(g) ↔ 2 HBr(g)
b) 2HCl(g) ↔ H2(g) + Cl2(g)
c) 2Mg(s) + O2(g) ↔ 2MgO(s)
d) CH4(g) + 4Cl2(g) ↔ CCl4(l) + 4 HCl(g)
Dr. Behrang Madani
Chemistry 100
IVC
10. Consider the quilibrium N2(g) + 3H2(g) ↔ 2NH3(g) at a certain temperature. An
equilibrium mixture in a 4.00 liter vessel contains 1.60 moles NH3, 0.800 moles N2, and 1.20
moles H2. What is the value of K?
11. Consider the reaction:
4HCl(aq) + MnO2(s) + Heat ↔ Cl2(g) + 2H2O(l) + MnCl2(aq)
In which direction (right or left) will the equilibrium position shift with the following
changes?
a) If a catalyst is added.
b) If pressure is lowered.
c) If temperature is lowered.
d) If H2O(l) is added.
e) If MnCl2 is removed.
12. The Ksp value for solid Al(OH)3 is 3.7×10-15 at 25°C. Calculate the solubility of Al(OH)3
in water at 25°C.
Dr. Behrang Madani
Chemistry 100
IVC
13. Approximately 0.14 g of nickel(II) hydroxide, Ni(OH)2(s), dissolves per liter of water at
20°C. Assume that Ni(OH)2 ionizes completely in water to Ni2+ and OH- ions. Calculate Ksp
for Ni(OH)2(s) at this temperature.
14. Find the oxidation state (oxidation number) for each element in the following
molecules/ions.
a) S in H2SO4?
b) C in Na2CO3?
c) Cr and C in Cr(C2H3O2)2?
d) P in HPO42- ?
e) Cr in HCr2O7- ?
15. Given the unbalanced equation below:
Fe2+(aq) + Cr2O72-(aq) + H+(aq) → Fe3+(aq) + Cr3+(aq) + H2O(l)
a. identify the oxidation state of each element
b. identify the oxidizing agent
c. identify the reducing agent
Dr. Behrang Madani
Chemistry 100
IVC
16. Given the unbalanced equation below:
B2O3(s) + Cl2(g) → BCl3(l) + O2(g)
a. identify the oxidation state of each element
b. identify the oxidizing agent
c. identify the reducing agent
17. Blance each chemical equation using half-reactions method.
a) BrO3-(aq) + Cu+(aq) → Br-(aq) + Cu2+(aq)
b) S2O82-(aq) + Cr3+(aq) → SO42-(aq) + Cr2O72-(aq)
c) MnO4-(aq) + C2O42-(aq) → Mn2+(aq) + CO2(g)
Dr. Behrang Madani
Chemistry 100
IVC