Question

The sum of the number of neutrons and protons in tritium is:

• A. 6
• B. 5
• C. 4
• D. 3

Answer 1

The correct option is D 3

Tritium ${(}_1^{3}H)$ is the isotope of hydrogen.
In the symbol, 1 represents the atomic number and 3 represents the mass number.
The number of protons is equal to the atomic number i.e., 1.
The mass number is the sum of protons and neutrons = $2+1$.
The sum of protons and neutrons $=$ $2+1$ $=3$.