Final answer:
The net ionic equation when HNO3 is added to the buffer HNO2 and NaNO2 is HNO3 + H+ + NO2- -> H2O + NO3-.
Step-by-step explanation:
The net ionic equation when HNO3 is added to the buffer HNO2 and NaNO2 is HNO3 + H+ + NO2- → H2O + NO3-. In this reaction, the nitric acid (HNO3) donates a hydrogen ion (H+) to the nitrite ion (NO2-) to form water (H2O) and nitrate ion (NO3-). The sodium ion (Na+) does not participate in the reaction and is considered a spectator ion.