Question

Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?
(i) Displacement reaction
(ii) Precipitation reaction
(iii) Combination reaction
(iv) Double displacement reaction

• A. (i) only
• B. (ii) only
• C. (iv) only
• D. (ii) and (iv)

Answer 1

The correct option is D (ii) and (iv)

$BaC{l}_2+(N{H}_4{)}_{2}S{O}_4$ $\to$ $BaS{O}_4+2N{H}_{4}Cl$

Above reaction is a double displacement reaction as ions (both cations and anions) of the reacting molecules are exchanged. Barium ion ($B{a}^{2+}$) combines with sulphate ion ($S{O}_4^{2-}$) to form Barium sulphate ($BaS{O}_4$) and ammonium ion $\left(N{H}_4^{+}\right)$ combines with chloride ion$(C{l}^{-}$) ion to form ammonium chloride ($N{H}_{4}Cl$).

The above reaction is also classified as a precipitation reaction because barium and sulphate ions combine to form precipitates of barium sulphate.
$B{a}^{2+}\left(aq\right)+S{O}_4^{2-}\left(aq\right)\to BaS{O}_4$(s)

Option D is correct.