Question

An ion M^+3 has 10 electron and 14 neutrons .find the atomic number and mass number of M?

Answer 1

When the charge is +3 means there is lose of 3 electrons .
In the question it says M^+3 has 10 electrons means when the atom is neutral I.e. no loss of electrons there will have been in total of 13 electrons
and in a neutral atom no. of electrons = no. of protons
so, atomic number will be 13.

neutron + protons = mass no.
14 + 13=27
so mass no. is 27 (Al)

Answer 2

M3+ is given

This symbolozes that the element is an ion .

No of electrons =10

So no of protons/atomic no=10+3=13

No of protons=14

So mass no =14+13

=27