He ngota, he rōpū ngota rānei kua whai whana hiko i roto i tētahi tauhohe matū. Mēnā ka ngaro tētahi irahiko, ētahi irahiko rānei o te ngota, ka kīia he whana tōrunga (+) nā te mea he nui ake ngā iraoho o te ngota i ngā irahiko. Mēnā ka hono mai tētahi irahiko, ka kīia he whana tōraro (‒) te ngota nā te mea he nui ake ngā irahiko i ngā iraoho.
An atom or group of atoms which have become charged during a chemical reaction. If an atom loses an electron, it becomes positively charged because it has more protons than electrons. If it gains electrons, it becomes negatively charged because it has more electrons than protons.