Give the ion symbol for the the ion that has 15 protons and 18 electrons

The symbol of the ion is

Explanation:

An ion is formed when a neutral atom looses or gains electrons.

Atomic number is defined as the number of protons or electrons that are present in a neutral atom.

Atomic number = number of protons = number of electrons

We are given:

Number of protons = 15

Number of electrons = 18

Charge = Number of protons - Number of electrons = 15 - 18 = -3

The element having 15 protons is phosphorus. So, the symbol of the ion is ion

Hence, the symbol of the ion is

plasma - state of matter made up of electrically charged particles