Question

An element X has mass number 23 and atomic number 11

state the number of neutrons in its nucleus.

Answer 1

Atomic number { Z}: Total number of an electron or proton in a neutral atom is considered an atomic number.

• The chemical properties of an element are determined by the number of protons in the nucleus.
• It is also known as the nuclear charge number.
• Atomic number = total number of electrons the total number of protons.
• Number of neutrons = mass number {A} - atomic number {Z}.
• Number of neutrons = 23 - 11.
• Number of neutrons = 12

Sodium: It is a chemical element with the symbol Na.

• Its atomic number is 11 and its mass number is 23, belongs to group 1st.
• It is a soft, silvery-white highly reactive alkali metal.
• Its only stable isotope is ${}_{11}{}^{}\mathrm{Na}$²³.

So, the total number of neutrons is 12