chemical reaction occurs when the chemical identity of the reactants is different from that of the products. A new substance forms with different properties from the original react
Evidence that a chemical reaction has occurred can be a color change, light formation, gas bubbles formation, precipitate formation, or temperature change,
Use the following information to answer question 1.
QUESTION 1
Instant cold packs consist of ammonium nitrate and water. When the two are mixed, the temperature changes and becomes colder. It is described using the chemical equation
NH4NO3(s) → NH4+ (aq) + NO3(aq)
LA
Is this an example of an endothermic or exothermic reaction? Why?

Exothermic: the surrounds feel warmer. A wood fire stove is a good example of an exothermic reaction. You can feel the heat on your hands. It's exothermic.

Endothermic is exactly the opposite. The reaction takes place, but the heat comes from the surroundings. When you touch something that goes through an endothermic reaction, it feels much cooler.

This reaction, just by definition is endothermic.

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