Answer:
a. NO₂⁻ + H⁺ → HNO₂
b. HNO₂ + OH⁻ → NO₂⁻ + H₂O
Explanation:
A buffer is defined as an aqueous mixture of a weak acid and its conjugate base or vice versa.
The buffer of the problem is HNO₂/NO₂⁻ where nitrous acid is the weak acid and NO₂⁻ is its conjugate base.
a. When a acid is added to a buffer as the buffer of the problem, the conjugate base will react with the acid, to produce the weak acid, thus:
NO₂⁻ + HCl → HNO₂ + Cl⁻
Ionic equation is:
NO₂⁻ + H⁺ + Cl⁻ → HNO₂ + Cl⁻
In the net ionic equation, you avoid the ions that don't react, that is:
b. In the same way, the weak acid will react with the strong acid producing water and the conjugate base, thus:
HNO₂ + NaOH → NO₂⁻ + H₂O + Na⁺
The ionic equation is:
HNO₂ + Na⁺ + OH⁻ → NO₂⁻ + H₂O + Na⁺
And the net ionic equation is:
