Question

The atomic mass of an element is equal to the number of:

1. protons
2. protons plus neutrons
3. protons plus electrons
4. neutrons

Answer 1

2. protons plus neutrons

Answer 2

Answer:

2

Explanation:

Atomic mass is actually comprised of the weight of Protons, Neutrons and Electrons. But Protons and Neutrons are approximately the same weight, electrons weight approximately 1835 times less than either and have a negligible influence on atomic weight. Hence, the atomic mass of an element is equal to the number of protons plus neutrons.