Matter: Chemical reactions transform one set of chemical substances into another. The total mass of the products is always the same as the total mass of the reactants, according to the law of conservation of mass.
Here are some examples of energy and matter transformations in chemical reactions:
- Combustion reactions release energy in the form of heat and light. For example, when you burn a piece of wood, the wood reacts with oxygen to produce carbon dioxide, water, and energy.
- Photosynthesis reactions absorb energy from the sun to produce glucose and oxygen. Plants use glucose for energy, and oxygen is released into the atmosphere.
- Digestion reactions break down food into molecules that the body can use for energy. For example, when you eat a piece of bread, the bread reacts with enzymes in your stomach and intestines to produce glucose, amino acids, and other nutrients.
Chemical reactions are essential for life and for many industrial processes. They allow us to convert energy from one form to another, and to transform matter into useful products.
