Provide an example of an exothermic and endothermic reaction.

An exothermic reaction is the combustion of methane, while an endothermic reaction is the melting of ice.

Exothermic reactions release energy in the form of heat, light, or sound. One example is the combustion of methane, which is a highly exothermic reaction. Methane reacts with oxygen to produce carbon dioxide and water, releasing a large amount of heat in the process. This reaction is used to generate energy in power plants and is also responsible for the heat and light produced by gas stoves.

Endothermic reactions absorb energy from their surroundings. One example is the melting of ice, which requires energy to break the bonds between water molecules and change the state of the substance from solid to liquid. This energy is typically supplied in the form of heat, which is why ice cubes placed in a warm room will eventually melt. Other examples of endothermic reactions include the evaporation of water and the decomposition of calcium carbonate.

Understanding the difference between exothermic and endothermic reactions is important in many fields, including chemistry, biology, and physics. By analysing the energy changes that occur during a reaction, scientists can gain insight into the underlying chemical processes and develop new technologies and materials.