1. Sulfanilic acid (NH2C6H4SO3H) has a pKa of 3.23. How manygrams of Na(NH2C6H4SO3) [182.1 g/mol] would you have to dissolve in125 mL of water to get a pH of 7.97?
a. 0.59
b. 1.2g
c. 3.5g
d. 4.8g
2. When KNO2 is dissolved in water, ___________.
a. [H3O+] = [OH-] |
| | |
| c. [H3O+] > [OH-] | | |
3. Calculate the concentration of HCN in a sol’n prepared bydissolving 10.8 g of NaCN (49 g/mol) in enough water to make 500.0mL of sol’n.  Ka for HCN = 4.0 x 10-10
| | 0.0057 M |
| | 0.0033 M |
| | 0.41 M |
| | 0.15 M |
4. What is the pH of a sodium formate (68 g/mol) solutionprepared by adding 0.680 g of sodium formate to 100.0 mL of waterat 25°C? The Ka for formic acid is 1.8 x 10-4 at 25°C.
5. Of the compounds below, a 0.10 M aqueous solution of ________will have the highest pH.
| | KCN, Ka of HCN = 4.0 x 10-10 |
| | NH4NO3, Kb of NH3 = 1.8 x 10-5 |
| | NaClO, Ka of HClO = 3.2 x 10-8 |
| | NaHS, Ka of H2S = 5.6 x 10-8 |
| | NaC2H3O2, Ka of HC2H3O2 = 1.8 x 10-5 |
