WAEC - Physics (2000 - No. 49)
The nucleon number and the proton number of a neutral atom of an element are 23 and 11 respectively. How many neutrons are present in the atom?
11
12
23
34
Explanation
Nucleon number = Proton number + Neutron number
Neutron number = Nucleon number − Proton number
Neutron number = 23 - 11 = 12
The number of neutrons present in the atom is 12