Question

A neutral atom of sodium (Na) has an atomic number of 11 and a mass number of 23. How many neutrons would be found in the nucleus of this atom of sodium?

Answer 1

12 neutrons

Step-by-step explanation:

• A neutral atom is an atom that has no charge, which means it has no additional electrons or electrons removed from its energy levels.
• An atom is made up of sub-atomic particles neutrons and protons found in the nucleus and electrons found in the energy levels.
• The number of protons in the nucleus of a neutral atom is known as the atomic number.
• In a neutral atom, the atomic number is equal to the number of electrons as protons are equal to the number of electrons.
• The sum of protons and neutrons in the nucleus of an atom is known as the mass number of an atom.

Therefore;

Protons = Atomic number

Protons + neutrons = Mass number

Thus;

Neutrons = Mass number - protons or

= Mass number - atomic number

In this case;

Atomic number = 11

Mass number = 23

Thus;

Neutrons = mass number - atomic number

= 23 - 11

= 12 neutrons