Question

When solid barium hydroxide and solid ammonium chloride are mixed in the test tube in a ratio of 2 : 1 by weight at room temperature then _______.
(A) reaction proceeds with rise in temperature
(B) reaction proceeds with fall in temperature
(C) no reaction takes place
(D) no reaction takes place unless heating is done

Answer 1

(B) reaction proceeds with fall in temperature

Mixing of solid barium hydroxide [Ba(OH)2] and solid ammonium chloride [NH₄Cl] in a ratio of 2 : 1 by weight at room temperature in a test tube sets an endothermic reaction and it proceeds by absorbing energy from the surrounding. Thus, there is a fall in temperature and especially the bottom of the test tube becomes cold.