Question

An ion which has a positive charge is called a:

Answer 1

An ion is composed of both positive and negative charges. A positive ion will be formed when an atom loses electrons. Negative ions will be formed when it accepts an electron.

Complete step by step answer:
Atoms can be subdivided into sub atomic particles. These are electrons, protons and neutrons. Electrons are negatively charged species. Protons are positively charged and neutrons and neutral.
Charged particles are called ions. These are formed when an atom loses or gains valence electrons. Positively charged ions are known as cations and negatively charged ions are known as anions. A cation will have more protons than electrons.
A cation will be formed when an atom loses the electrons. As the number of electrons, its losses increase then the positive charge will also increase.

Additional information:
Cation will have positive charge, so it will get attracted to negatively charged electrodes. Anions are negatively charged so they will get attracted to positively charged electrodes. When we move down a group. Size of the atom increases. So, the attraction of the nucleus on the electron decreases. That means ionization energy decreases. So, the electron can be removed easily. So, as we move down the group. The tendency to form cation increases. When we move across a period size of the atom decreases so ionization energy will decrease. Hence, the tendency to form cation decreases along the period. Size of the cation will be smaller than anions. So, in solids, cations can occupy the interstitial positions.

Note: Acidic strength of complexes depends upon the positive charge. As the positive charge increases acidic strength will increase. Non-metals usually form anions e.g. ${O^{2 - }}$ . Alkali and alkaline earth metals will always form cations. Halogens will form anions.
Example for cations: $M{g^{2 + }}$ , $Z{n^{2 + }}$ , $N{a^ + }$ etc.
Example for anions: $O{H^ - }$ , $C{N^ - }$ , $C{l^ - }$ etc.