Explanation:
HNO₂ ionizes in the following way -
HNO₂ + H₂O ----> H₃O⁺ + NO₂⁻
Hence , if we add ions of NO₂⁻ , it will increase the concentration of these ions towards the right side , and the reaction will proceeds in the backward direction , because of the Le - Chateliers principle ,
Hence from the options given in the question , none will be able to bring the reaction , back , i.e. reduce the ionization .
But in case we use KNO₂ , then , it is capable to reduce the ionization of HNO₂ .
