Question

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. The temperature at the start of the reaction was 23.0°C and at the end it was 18.5°C. Was this an exothermic or an endothermic reaction?

endothermic
exothermic

Answer 1

Endothermic.

Step-by-step explanation:

Because the temperature decreased, the reaction is endothermic.

Endothermic reactions absorb heat from the surroundings. In this case, the dissolution of the ammonium nitrate absorbed heat from the surroundings (the water). Hence, the temperature of the solution decreased.