Question

2. As the pKa of an acid increases, the acid will be
A. More weaker. B. More stronger C. Converted to neutral solution. D. Converted to basic
solution​

Answer 1

As the pKa of an acid increases, the acid will be more weaker.

• the pH of an acid is inversely proportional to its pKa.
• That means if we increase the acidity or pH of a solution the pKa value decreases.
• Thus if the pKa of acid increases then the pH of the corresponding acid decreases so, the acidity of the acid also decreases and it becomes weaker.
• Hence the correct option is A.

Answer 2

OPTION (A) IS CORRECT.

(A) MORE WEAKER

Explanation:

• The $pK_{a}$ value is calculated by using the formula: $pK_{a}=-logK_{a}$ .
• The $K_{a}$  value is directly proportional to the acidic strength of an acid and indirectly proportional to $pK_{a}$ value.
• A stronger acid will have higher $K_{a}$  value and less $pK_{a}$  value.
• A weaker acid will have lower $K_{a}$ value and higher $pK_{a}$  value.
• Therefore, as $pK_{a}$  value increases, the acid becomes weaker. Hence, option (A) is correct.