Chapter 2, Problem 91AP

Interpretation Introduction

Interpretation:

The chemical symbol for the anionhaving $18$ electrons is to be determined.

Concept introduction:

The number of protons present in the nucleus or number of electrons that revolve around the nucleus is called the atomic number. It is indicated by the letter ‘Z’. The atomic number of an atom is calculated by subtracting the number of neutrons from the mass number. The relation between the number of neutrons, mass number and atomic number is as follows:

$\text{Atomic}\text{number}\left(Z\right)=\text{Mass}\text{number}\left(A\right)-\text{Number}\text{of}\text{neutrons}$

The gain of one or more electrons by an atom yields an anion.