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) NH4Cl 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) Na2CO3 and CH3COOHNa will give basic solutions because they created from a strong base and weak acid --- pH>7