He tūhononga ngota. Te hanga iti rawa atu o tētahi pūmotu, o tētahi pūhui rānei e taea ana. Kei roto i te tohu mō te rāpoi ngota e whakaaturia ana te maha o ia ngota e hono ana hei hanga i te pūmotu, i te pūhui rānei. Hei tauira, ko te rāpoi ngota wai (H2O). E rua ngā ngota hauwai (H) ka hono atu ki tētahi ngota hāora (O) kotahi. I te paemahana ā-whare, ka noho takirua ngā ngota o te hauwai (H), arā, ko te tohu H2.
A bonding together of atoms. The smallest possible configuration of elements or compounds. The symbol for a molecule shows the number of atoms that are joined to form the element or compound. For example, a water molecule (H2O) is made up of two hydrogen atoms bonded to a single oxygen atom. At room temperature, hydrogen (H) atoms exist as bonded pairs, giving rise to the symbol H2.