Question

The sum of protons,electrons and neutrons in the heaviest isotope of hydrogen is

• A. 6
• B. 5
• C. 4
• D. 3

Answer 1

Answer: (C)

4

Answer 2

The heaviest isotope of hydrogen is tritium ${ }_{1} T ^{3}$ with atomic number 1 and mass number 3 . It contains 1 electron, 1 proton and 2 neutrons. The sum is $1+1+2=4$.