Question

The composition of an atom P is 13. 11. 11 . What is the mass number?

Answer 1

Dear Student..

To do this question we need to know these two things...

1) In an atom, number of electrons and protons are equal

2)
Mass no = No. of protons + No. of neutrons.


Here two equal value given are 11, 11
So number of electrons and protons are 11

And the remaining 13 is the number of neutrons


So,
Mass no =13 + 11
= 24