Question

What is the mass number of an atom which contains 28 protons, 28 electrons and 34 neutrons?

Answer 1

mass no.= no. of protons + no. of neutrons

= 28 + 34

= 62

Answer 2

Answer:

The mass number of the atom = $62$.

Explanation:

Given,

The number of protons, $n_{p}$ = $28$

The number of electrons, $n_{e}$ = $28$

The number of neutrons, $n_{n}$ = $34$

The mass number of the atoms =?

As we know,

• The mass number is defined as the sum of the number of protons and the number of neutrons.
• The electrons are not included because they have almost negligible mass and are considered nearly equal to zero.

Therefore,

• Mass number = $n_{p}+n_{n}$
• Mass number = $28 + 34$ = $62$

Hence, the mass number of the atom = $62$.