Question

An atom has a mass number of \[25\] and \[13\] neutrons. What is the atomic number of this atom?

Answer 1

Hint: Atom is a tiny particle consisting of subatomic particles. Atoms combine to form molecules. Every atom has an electron, proton and neutron. The atomic mass number gives the number of protons. The mass number gives the sum of both neutrons and protons. The difference between the mass number and atomic number gives the number of neutrons.

Complete answer:
Periodic table is the representation of chemical elements in the increasing order of atomic numbers. The elements are arranged in the vertical columns and horizontal rows. The vertical columns were known as groups and the horizontal rows were known as periods. There are a total of \[118\] elements in \[7\] periods and \[18\] groups.
Atoms are tiny particles consisting of three subatomic particles like electrons, neutrons and protons. The atomic number gives the number of protons and the mass number gives the sum of the protons and neutrons.
Given that an atom has a mass number of \[25\] and \[13\] neutrons. The difference of the neutron number from the mass number gives the atomic number.
Thus, the atomic number of atom is \[25 - 13 = 12\]
An atom has a mass number of \[25\] and \[13\] neutrons. The atomic number of this atom is \[12\]

Note:
The atom with atomic number \[12\] is magnesium. It belongs to an alkaline earth metal. Being a metal magnesium can easily lose electrons and can be considered as a metal. Magnesium forms salts when reacted with halogens. Magnesium can be used in crackers making.