A substance that consists of atoms of only one kind is known as what?

A substance that consists of atoms of only one kind is recognized as a chemical element. Chemical elements are pure substances that cannot be broken down into simpler substances by chemical means. Each element is defined by the number of protons in its nucleus, which is known as the atomic number. For instance, all atoms of hydrogen contain one proton, while all atoms of carbon contain six protons.

This concept is fundamental in chemistry as it distinguishes elements from compounds and mixtures. Compounds are composed of two or more different types of atoms chemically bonded together, while mixtures contain two or more substances that are physically combined but not chemically bonded. Molecules typically refer to groups of two or more atoms bonded together, which can include different elements as well. Understanding that a chemical element only contains one kind of atom is crucial in identifying and categorizing substances in the field of chemistry.