The order of acid strength is:
1. HNO2 > HOCl > HNO3 > NH4+
2. HOCl >HNO3> NH4+ > HNO2
3. HNO3 > NH4+ > HNO2 > HOCl
4. HNO3 > HNO2 > HOCl > NH4+
Correct Answer: 4.
Comments to the instructor: You may or may not allow students to use a table of Ka’s, or
provide Ka’s as a hint. If students know that HNO3 is a strong acid, then the choices 1
and 2 may be quickly eliminated.
The order of increasing base strength is:
1. H2O > NH3 > CH3CO2- > CN-
2. NH3 > H2O > CH3CO2- > CN-
3. NH3 > CN- > CH3CO2- > H2O
4. CH3CO2- > NH3 > CN- > H2O
Correct Answer: 3.
Comments to the instructor: A table of Ka’s is useful.
The order of increasing acid strength is:
1. H2SO4 > HSO4- > H3PO4 > H2PO4- > HPO42-
2. HSO4- > H2SO4 > H3PO4 > H2PO4- > HPO42-
3. H3PO4 > HSO4- > H2SO4 > H2PO4- > HPO42-
4. H3PO4 > H2SO4 > HSO4- > H2PO4- > HPO42-
