Question

An atom has mass number A and atomic mass Z
1) How many protons present in the nucleus?
2) How many electrons revolve around the nucleus?
3) How many nuetrons present in the nucleus?​

Answer 1

1.) No of protons present are same as atomic number i.e, Z
2.)electrons revolve around nucleus are Z as atomic number =number of protons=number of electrons
3.)neutrons present are :- Mass number(Z) -No of protons(p)