Exam 3B, Spring 2000

1. Complete and balance the following reactions:

a C5H11N(aq) + H2O(l)

b (CH3)2NH(aq) + HOBr(aq)

c Fe2+(aq) + H2O(l)

d Cr(NO3)3(aq) + K3PO4(aq)

e Ca(C2H3O2)2(aq) + H2SO4(aq)

f Zn(NO3)2(aq) + NH3(aq)

2. Consider a 0.65 M solution of triethylamine, (C2H5)3N, at 25 °C.

a. Find the pH of the solution.

b. Enough triethylammonium chloride, (C2H5)3NHCl, is added to the solution to make the concentration of the triethylammonium ion 0.70 M. Find the pH of this buffer.

c. 5.0 g of perchloric acid is added to 1.0 L of the buffer prepared in part b. What is the new pH?

3. Consider silver bromide at 25 °C.

a. What is the molar solubility of silver bromide in pure water?

b. What is the molar solubility of silver bromide in 0.035 M sodium bromide solution?

c. What is the molar solubility of silver bromide in 1.0 M ammonia solution?

4. Indicate whether the following salts are acidic, basic, or neutral.

a. NH4NO3

b. Mn(OH)2

c. Mn(HSO4)2

d. NaC2H3O2

e. NaClO4

Answers