Practice for Acids, Bases and Salts
1. Find the pH and pOH for a solution made by adding 5.00 moles of LiOH to 2.00L
of water.
2. Find the pH and pOH for a solution made by adding 5.00 moles of HBr to 0.50L of
water.
3. Find the pH of .300M HF. The Ka for HF is 7.2 x 10-4.
4. Find the pH of 0.295M C2H5NH2. The Kb is 5.6 x 10-4.
5. If a 0.0500M solution of HC2H3O2 has a pH of 3.03, what is the Ka value?
6. Calculate the Kb of .10 M pyridine, C5H5N, which has a pH of 12.35.
7. The pH of a 0.01 M phosphoric acid solution is approximately
a. 1
b. 3
c. 7
d. 11
e. 13
8. H3PO4 is a _________________acid and H3PO4 is a __________________acid than H2PO4- and
H2PO4- is a ____________________ acid than HPO4-2.
a. strong, stronger, stronger
b. weak, weaker, weaker
c. weak, stronger, stronger
d. strong, weaker, stronger
e. strong, weaker, weaker
9. Which one of the following salts when added to pure water will not change the
pH of the solution?
a. CsBr
b. Mg3N2
c. NaH2PO4
d. NH4NO3
e. Fe(NO3)3
10. One molar solutions of the following three salts: Na3PO4, Al(NO3)3 and NH4Cl –
will result in solutions which are respectively
a. basic, neutral, acidic
b. basic, acidic, acidic
c. acidic, basic, neutral
d. acidic, acidic, neutral
11. Arrange the following 0.10 M solutions in order from most acidic to most basic,
you may need to look up k values.
CaBr2,
KNO2,
HClO4,
HNO2,
HONH3ClO4
12. The Kb values for ammonia and methylamine are 1.8 x 10-5 and 4.4 x 10-4,
respectively. Which is the stronger acid, NH4+ or CH3NH3+?
13. Calculate the pH, [H+] and [OH-] of the following solutions.
a. 0.10 M CH3NH3Cl
b. 0.050 M NaCN
14. Explain why HF is a weak acid while HCl, HBr and HI are all strong acids.
15. Explain why acid strength increases in the following series:
HClO, HClO2, HClO3, HClO4
16. Solve the mystery! What is the salt that is dissolved in water? When .100 mole
of the salt is dissolved in 1.00L of solution, the pH is 8.88. What is the identity of the
salt? Choose from the following: NaCN, NaC2H3O2, NaF, NaCl, or NaOCl.
Acid
HCN
HC2H3O2
HF
HCl
HOCl
Ka
6.2 x 10-10
1.8 x 10-5
7.2 x 10-4
Huge!!
3.5 x 10-8