Atoms and molecules are the basic building blocks of all “normal” matter in the universe. They make up everything from the simple chemical bonds of water to complex structures like humans. Atoms and molecules have different charges and configurations which create different structures with different properties.
An atom consists of a dense central nucleus that is surrounded by a “cloud” of negatively charged electrons. The nucleus contains positively charged protons and neutral neutrons. The electrons are bounded in the nucleus by an electromagnetic force. Atoms will group together by chemical bonds based on the force of the atoms to create chemical bonds.
Atoms will be positive, negative or neutrally charged based on the number of protons and electrons. If an atom is positive or negatively charged it is referred to as an ion. Atoms are classified based on the number of protons and neutrons in the nucleus. Atoms can be different sizes with respect to the number of proton, neutrons and electrons in the atomic configuration.
A molecule is an electrically neutral group of two or more atoms that are held together by covalent chemical bonds. Molecules are different from ions due to the neutral charge they maintain. Molecules, like atoms, can take on different sizes and configuration based on the type of atoms and the length of the bonds. Molecules are distinguished by their molecular formula, which is defined by the ratio of atoms involved in creating the molecule.