Give one example each of a salt which gives an aqueous solution having :

(a) pH less than 7

(b) pH equal to 7

(c) pH more than 7

(a) $N{H}_{4}Cl$ will give an acidic solution because it is made up of a strong acid and weak base --- $pH<7$

(b) $NaCl$ will give a neutral solution because it is made up of a strong base and strong acid --- $pH=7$

(c) $N{a}_{2}C{O}_{3}andC{H}_{3}COOHNa$ will give basic solutions because they created from a strong base and weak acid --- $pH>7$