Question

Take about 2g barium hydroxide in a test tube add 1g of ammonium chloride and mix with help of a glass rod touch the bottom of test tube, is this an exothermic or endothermic reaction

Answer 1

When $1g$ of Ammonium chloride$\left(N{H}_{4}Cl\right)$ is added to a testube containing $2g$ of Barium hydroxide$\left(Ba\right(OH{)}_2)$, leading to the formation of Barium chloride$\left(BaC{l}_2\right)$ along with Ammonium hydroxide$\left(N{H}_{4}OH\right)$.

$Ba(OH{)}_2+2N{H}_{4}Cl\to BaC{l}_2+2N{H}_{4}OH$

When we mix barium hydroxide with ammonium chloride, the bottom of the test tube becomes cold due to the absorption of heat. So, it is an endothermic reaction.

Hence, this reaction is an endothermic reaction.