At exceedingly high temperatures, the atoms of matter are shaken apart creating a state of matter called plasma. Our Sun and other stars are in the plasma state. Nitrates in the soil are a source of nitrogen needed by the plant to make protein. Magnesium is a mineral needed by plants to make chlorophyll. Calcium is a mineral needed by humans for bone growth.
Atoms are the fundamental building blocks of molecules.
A molecule is any group of atoms that are bonded together and act as a unit. Hydrogen and oxygen do not always bond to form water. Two atoms of hydrogen and two atoms of oxygen can bond to form hydrogen peroxide. While the periodic table has about 100 different chemical elements, these can combine in different ways to form tens of millions of different molecules. This type of defective vision usually results from an eyeball which is too long.