Question

Which statement describes how NO2- reacts in this equilibrium:

Answer 1

The statement which describes how NO2- reacts in this equilibrium:
H2SO3(aq) + NO2-(aq) HSO3-(aq) + HNO2(aq
is the second option - B. as a Brønsted-Lowry base by accepting a proton.
This is because bases take proton H+ in order to become HNO2. 

Answer 2

Answer : Option B) as a Brønsted-Lowry base by accepting a proton.

Explanation : In the given reaction $H_{2}SO_{3}_{(aq)} + NO_{2}^{-}_{(aq)} ----> HSO_{3}^{-}_{(aq)} + HNO_{2}_{(aq)}$

According to the Bronsted-Lowry theory of acids and bases, the formation of conjugate acids and bases forms the central theory.

Wherein, the conjugate base is the ion or molecule which remains after the acid has lost its proton, and the conjugate acid is the species which is created when a base accepts that proton.

In the given question $NO_{2}^{-}$ is the species which is acting as a Bronsted-Lowry base, as this the species which is accepting a proton and getting converted into $HNO_{2}$.