Question

Which of the following do not have THE SAME NUMBER OF PROTONS AND NEUTRONS? 14C 12C 2H 16O

Answer 1

Number of neutrons = mass number - atomic number of element.

14 C , C has atomic number 6 which means protons = 6 , neutrons = 14-6 = 8

hence protons not equal to neutrons

12C has 6 protons and neutrons = 12-6 = 6 ,hence number of protons = number of neutrons

2H , H has atomic number 1 hence 1 proton, number of neutrons = 2-1= 1,

16O , O has atomic number = 8 , hence 8 protons , number of neutrons = 16-8 = 8

Hence 14C doesnot have same number of protons and neutrons. ( remaining all have protons = neutrons)