Question

If an ion of an element has 2 positive charges , the mass no. of the atom is 24 and the no. of neutron is 12. State the no. of electrons in the ion ?

Answer 1

Hey!

Let that element be X and that ion be X^2+
Here It's given that ,
Mass number ( A ) = 24
Number of neutrons ( n ) = 12

We fairly know that ,
Mass number ( A ) = no: of p + no: of n
Where , p & n stands for protons and neutrons
From the given data it's easy for us to calculate the no: of protons.
i.e ,
No : of p = A  - ( no: of neutrons )
= 24 - 12
= 12 //
Since no: of protons in an atom is equal to number of electrons in it.
No: of electrons will also be 12.

Since this ion have deficiency of 2 electrons ( it donates 2 electrons , that resembles its  ' +2 ' charge )

.: Number of electrons in that ion = 12 - 2
Which is equal to 10 //

Answer 2

Answer:

10

Explanation:

Mass Number = Atomic Number (or number of protons) + Number of neutrons

Thus, Atomic number = Mass number - number of neutrons

                                        = 24 - 12

                                        = 12

Thus, there are 12 protons. So, there should be 12 electrons in the neutral atom.

Since, it is not an atom, but an ion with 2+ charge, it means it has two electrons less.

So, there are 10 electrons in the ion.