Respuesta :
Answer : This is an endothermic reaction.
Explanation :
Endothermic reaction : When the system absorb heat from the surrounding then the surrounding become cool.
Exothermic reaction : when the system releases heat into the surrounding then the surrounding become hot.
So, when ammonium chloride is dissolved in water then the beaker gets cold. That means the system is absorbing heat from the surrounding and thus the reaction is an endothermic reaction.
