Question

In the given pair, which is a stronger base?

${NO}_2^{-},{NO}_3^{-}$

• A. ${NO}_2^{-}$ $>$ ${NO}_3^{-}$
• B. ${NO}_2^{-}$ $<$ ${NO}_3^{-}$
• C. ${NO}_2^{-}$ $=$ ${NO}_3^{-}$
• D. None of these

Answer 1

Answer: (A)

${NO}_2^{-}$ $>$ ${NO}_3^{-}$

$H{NO}_3$ contains the number of electronegative oxygen atoms than $H{NO}_2$.

Due to this, the negative charge (obtained due to dissociation of a proton) is

more stabilized in ${NO}_3^{-}$ than in ${NO}_2^{-}$.

Hence, the correct order of the acid strength is $H{NO}_2<H{NO}_3$.

Now the conjugate base of a strong acid is a weaker base.

So, the correct order of basicity is ${NO}_2^{-}>{NO}_3^{-}$.