What is the Atomic Mass of Hydrogen?

Atomic Mass of Hydrogen is  _____________.

A)  2

B)  3

C)  1

D)  4

Answer: The atomic mass of Hydrogen is 1 amu. Therefore, the correct option is C.

Explanation:

Atomic Mass of any substance is the number of Nucleons i.e. the sum of the Number of Protons and the Number of Neutrons in the nucleus of that atom.

For Hydrogen,

• Number of Protons = 1
• Number of Neutrons = 0

Thus,

Atomic Mass of  Hydrogen = 0 + 1 = 1 amu

Hydrogen is the only known element that has no neutrons in its nucleus in its stable form.

In absolute terms, the average atomic mass of Hydrogen is 1.00784 amu. It is calculated taking into account all the isotopes of Hydrogen. There are three isotopes of Hydrogen: Hydrogen (₁H¹), Deuterium(₁H²) and  Tritium(₁H³). They each have a single proton.