What is an example of an everyday endothermic reaction in which bonds are broken?

An example of an everyday endothermic reaction in which bonds are broken is the process of dissolving ammonium nitrate in water. The dissolution of ammonium nitrate requires the breaking of bonds between the ammonium (NH4+) and nitrate (NO3-) ions. This reaction is commonly observed in the preparation of instant cold packs.

To understand why this reaction is endothermic and how the bonds are broken, we can break it down into steps:

1. First, the solid ammonium nitrate (NH4NO3) is added to water (H2O).

2. As the solid dissolves, the water molecules surround and interact with NH4+ and NO3- ions. This process is called solvation.

3. To dissolve ammonium nitrate, energy is required to break the intermolecular forces that hold the solid together. These forces include ionic bonds between ammonium and nitrate ions.

4. Breaking these bonds requires an input of energy, which is absorbed from the surrounding environment. Therefore, this reaction is endothermic.

5. As energy is absorbed, the temperature of the surroundings decreases, resulting in the "cold" sensation often associated with cold packs.

By understanding the concept of bond breaking and the requirement of energy input, you can explore various everyday processes and reactions to identify other examples of endothermic reactions involving bond-breaking.