Question

We can represent an atom by the symbol ${}_{\mathrm{z}}{}^{\mathrm{A}}\mathrm{X}$. Give the meaning of
(i) X
(ii) A
(iii) Z

Answer 1

Atom:

1. The smallest unit of ordinary matter that makes up a chemical element is an atom.
2. An atom is made up of protons, electrons, and neutrons.
3. An atom can be written in the form ${}_{\mathrm{z}}{}^{\mathrm{A}}\mathrm{X}$.

Here,
(i) X represents the atomic symbol of any element.
(ii) A represents the mass number (total number of protons and neutrons).
(iii) Z represents the atomic number (number of electrons or protons).