Electrons are super important when it comes to chemical reactions because they help change energy. Atoms are made up of three parts: protons, neutrons, and electrons. The electrons we focus on the most are the ones found in the outer layer, called valence electrons. These are the electrons that interact when reactions happen.

How Electrons Change Energy:

1. Making and Breaking Bonds: When a chemical reaction takes place, bonds between atoms either break apart or form new ones. This involves rearranging electrons:

   • Exothermic Reactions: In these types of reactions, like burning fuel, more energy is released when new bonds form than what it takes to break the old ones. For example, when methane (a type of gas) burns, it gives off a lot of energy to create carbon dioxide and water, more than what is needed to break its bonds.
   • Endothermic Reactions: In these reactions, like when plants make food in photosynthesis, more energy is taken in than what is given off. Energy is needed to break the bonds in materials like carbon dioxide and water.

2. Electron Transfer: In redox reactions, electrons move between atoms. This movement changes the oxidation states, which is important in things like batteries and the way our cells get energy (cellular respiration).

3. Electron Arrangement: The way electrons are organized in an atom impacts how that atom connects with others. For example, elements that are in the same column of the periodic table tend to behave similarly because they have similar arrangements of valence electrons.

In short, understanding how electrons work helps us see how energy changes during chemical reactions. This knowledge helps explain everything from what happens in our daily lives to complex processes in living things.