Which statement best explains why hydrogen’s atomic number is equal to its mass?(1 point)

Question

Responses

Hydrogen is in the first row and the first column of the periodic table.
Hydrogen is in the first row and the first column of the periodic table.

Hydrogen only has one electron
Hydrogen only has one electron

Hydrogen is stable, with two electrons in its outer shell.
Hydrogen is stable, with two electrons in its outer shell.

Hydrogen does not have any neutrons.

Answer 1

The statement that best explains why hydrogen's atomic number is equal to its mass is:

Hydrogen does not have any neutrons.

Hydrogen has an atomic number of 1, which means it has one proton and, in its most common isotope, no neutrons. The atomic mass of this isotope (protium) is approximately 1, because the mass number is the sum of the protons and neutrons, and in this case, it is 1 (from the single proton).