Which of the following is an endothermic process?

Question

dissolving acetic acid in water

rusting a nail in water

thawing frozen shrimp

mixing strong hydrochloric acid and strong ammonium hydroxide

Answer 1

The question tests whether the student knows that an endothermic process requires the input of energy and therefore does not progress spontaneously. Of these four, three will proceed without the input of additional energy however the thawing of shrimp will not happen without energy received presumably from the environment. It's an off question, but that's the answer.