Question

Which of the following reactions are examples of double displacement reactions but not precipitation reactions?

(I) NaOH + H2SO4 → Na2SO4 + H2O

(II) CuO + 2HCl → CuCl2 + H2O

(III) AlCl3 + 3NH4OH → Al(OH)3 + 3NH4Cl

(IV) CuSO4 + H2S → CuS + H2SO4

(a) Both (I) and (II)

(b) Both (I) and (III)

(c) Both (II) and (III)

(d) Both (II) and (IV)​

Answer 1

Answer:

D

(b) & (d)

BaCl

2

(aq)+Na

2

SO

4

(aq)→BaSO

4

(s)+2NaCl(aq)

The types of reactions are (b) Precipitation and (d) Double displacement.

A precipitate of bariumsulphate is obtained.

In double displacement reaction, two compounds react, and the positive ions (cation) and the negative ions (anion) of the two reactants switch places, forming two new compounds or products.

So, the correct option is D.