Question

Note whether the aqueous solution of each of the following salts will be acidic, basic or neutral. Note why.

a.   Na2S

b.   Cu(NO3)2

c.   KNO3

d.   CH3NH3Cl

Answer 1

The nature of aqueous solution will be dominated by either strong acid or strong base.

a.   Na2S + 2H2O -------> 2NaOH(aq) + H2S(aq)

The solution will have strong base NaOH and weak acid H2S, hence solition will be basic.

b.   Cu(NO3)2 + 2H2O ------> Cu(OH)2(aq) + 2HNO3(aq)

The solution will have weak base Cu(OH)2 (as Cu is transition metal ) and strong acid HNO3, hence solution will be acidic.

c.   KNO3 + H2O -----> KOH(aq) + HNO3(aq)

The solution will have strong base KOH and strong acid HNO3, hence solition will be neutral.

d.   CH3NH3Cl + H2O ------> CH3NH2(aq) + HCl(aq)

This solution will have weak base CH3NH2 and strong acid HCl, hence solition will be acidic.