Question

Which has the highest $pH$?

• A. $C{H}_{3}COON{H}_4$
• B. $N{a}_{2}C{O}_3$
• C. $N{H}_{4}Cl$
• D. $NaN{O}_3$

Answer 1

Answer: (B)

$N{a}_{2}C{O}_3$

(A) ${CH}_{3}COO{NH}_4$

${CH}_{3}COOH$ $K$ weak acid $pH$ is close to $7$.

${NH}_{4}OH$ is weak base

(B) ${Na}_2{CO}_3$

$NaOH$ is strong base $pH>7$

(C) ${NH}_{4}Cl$

$HCl$ is strong acid $pH<7$

(D) ${NaNO}_3$

$NaOH$ is strong base $pH$ is close to $7$.

${HNO}_3$ is strong acid

$\Rightarrow {Na}_2{CO}_3$ has the highest $pH$.