Question

The given reaction of \[Ba(OH){_2} + 2N{H_4}Cl\] is endothermic/exothermic.

Answer 1

Hint: To understand the question we must know what exothermic and endothermic reaction is. Exothermic reactions transfer energy to the surroundings and the temperature of the surroundings increases. Endothermic reactions take in energy and the temperature of the surroundings decreases. For further explanation refer to the solution.

Complete answer:
Ammonium chloride reacts with barium hydroxide to form ammonia. Reaction between barium hydroxide ammonium chloride is a double displacement gas evolution reaction. The products of this reaction are Barium Chloride, Ammonia and Water.
\[Ba{(OH)_2} + 2N{H_4}Cl \to BaC{l_2} + 2N{H_3} + 2{H_2}O\]
This reaction is an endothermic reaction. Endothermic reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products. Physical processes can be endothermic as well. Ice cubes absorb heat energy from their surroundings and melt to form liquid water.
Ammonium Chloride is slightly acidic and Barium Hydroxide very basic. In an endothermic reaction, the $\Delta H$ is positive corresponding to the absorbed heat. Thus this positive $\Delta H$ must be offset by a sufficient increase in entropy.

Additional information:
Ammonium Chloride is a systemic and urinary acidifying salt. Ammonium chloride helps maintain pH and exerts a mild diuretic effect. This acid forming salt also exerts an expectorant effect by irritating the mucous membranes and is used for alleviation of cough. Ammonium chloride is a white crystalline solid.

Note:
The given reaction is a double displacement reaction. Reactions in which two compounds react by an exchange of ions to form two new compounds are called double displacement reactions. In double replacement reactions, the positive ions exchange negative ion partners. Many double displacement reactions occur between ionic compounds that are dissolved in water.