At a concentration of 1 M, the weak acid HNO 2 is 2% ionized, and the pH of the solution is 1.7. What happens when KNO 2 ( s ) is dissolved into the solution

Le-Chatelier's principle : This principle states that if any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

The dissociation reaction of [tex]HNO_2[/tex] is:

[tex]HNO_2\rightleftharpoons H^++NO_2^-[/tex]

As we are adding [tex]KNO_2[/tex] that means increase the concentration of [tex]NO_2^-[/tex] then the equilibrium will shift in the left direction.

If the concentration of [tex]NO_2^-[/tex] is increased on product side then the equilibrium will shift in the direction where decrease of concentration of

Hence, when [tex]KNO_2[/tex] dissolved into the solution then the equilibrium will shift in the left direction.

Manetho Manetho · Answer 2 · 2020-02-12T12:24:15+01:00

Manetho Manetho

12-02-2020

Explanation:

The reaction can be written as

HNO_2 ⇔H+ + NO2-

Now, adding KNO2 will further increase the conc. of NO2-.

Now, As per Le Chatelier's principle the equilibrium will shift reactant side as its conc. is decreased.

This reduces the extent of ionization of HNO2. Hence, Concentration H+ ion decreases.

And also, pH= -log[H+]

hence, pH increases.

Answer Link