Question

If mg2+ has 12 proton 12 neutron, what is its atomic number and mass number?

Answer 1

it had 12 protons so, no.of proton is equal to atomic no. therefore it's atomic no will be 12
it mass no. will be 24
as 12 +12= 24 because mass no. equal to sum of no. of proton and no. of neutron

Answer 2

Given : A Mg²⁺ ion has 12 protons and 12 neutrons.

To find : The atomic number and the mass number of It.

solution :

• cation : when an element loses electrons from its outermost orbit, it forms cation.
• anion : when an element accepts electrons to its outermost orbit , it forms anion.
• atomic number : number of protons in an atom.
• mass number : The sun of number of protons and neutrons is known as mass number.

here Mg²⁺ ion forms after losing two electrons from its ground state.

number of protons = atomic number

here, number of protons = 12

Therefore atomic number of Mg, Z = 12

mass number = number of protons + number of neutrons

= 12 + 12

= 24

Therefore the mass number of Mg is 24.