Question

Pick out the correct statement.

• A. Compared to a strong acid, a weak acid titration with base starts at a higher pH
  
• B. Compared to a strong acid, a weak acid titration with base starts at a lower pH
  
• C. $HCN(aq.)+{NO}_2^{-}(aq.)⟶H{NO}_2(aq.)+{CN}^{-}(aq.)$
• D. None of these

Answer 1

The correct option is A Compared to a strong acid, a weak acid titration with base starts at a higher pH

$HN{O}_2$ is a stronger acid than $HCN$ so this reaction will go backward as every reaction have the tendency to go towards the weak acid-weak base.

$HCN(aq.)+{NO}_2^{-}(aq.)⟶H{NO}_2(aq.)+{CN}^{-}(aq.)$

From the titration curve it can be seen that,

compared to a strong acid, a weak acid titration with base starts at a higher pH.