Chemistry MCQ Practice

All ammonium salts on heating with sodium hydroxide produce ammonia gas.

 

For which ammonium salt can the greatest mass of ammonia be obtained?

 

A)  0.5 mol (NH₄)₃PO₄

 

B)  0.5 mol (NH₄)₂SO₄

 

C)  1.0 mol NH₄Cl

 

D)  1.0 mol NH₄NO₃

 

 

Answer: A

 

Ionic eqn: NH₄⁺ + OH⁻ → NH₃ + H₂O
→ 1 mol NH₄⁺ will produce 1 mol NH₃

 

- the larger the no. of moles of NH₄⁺ present, the larger the no. of moles of NH₃ produced, the greater the mass of ammonia obtained.

 

No. of moles of NH₄⁺ present in:
A = 0.5 x 3 = 1.5 mol
B = 0.5 x 2 = 1.0 mol
C = 1 x 1 = 1.0 mol
D = 1 x 1 = 1.0 mol