Chemical compounds are substances made up of two or more elements that are chemically bonded. Some of the most common chemical compounds in everyday life include water (H2O), table salt (NaCl), and carbon dioxide (CO2). These compounds are formed through chemical reactions, where atoms of different elements join to form new substances.
Chemical compounds are essential to many processes on Earth. For example, water is crucial for life, salt is vital for human nutrition, and carbon dioxide is produced during respiration. Understanding these compounds is key to chemistry, as they make up much of the matter around us, from the air we breathe to the food we eat.