7. Molecules of water are

Explanation: Water is a chemical compound and polar molecule, which is liquid at standard temperature and pressure. It has the chemical formula H2O, meaning that one molecule of water is composed of two hydrogen atoms and one oxygen atom. Water is found almost everywhere on earth and is required by all known life.

oxygen atom and two hydrogen atoms

Explanation:

A water molecule consists of three atoms; an oxygen atom and two hydrogen atoms, which are bond together like little magnets. The atoms consist of matter that has a nucleus in the centre. The difference between atoms is expressed by atomic numbers.