Question

a neutral atom has an atomic mass of 16 amu. which particles contribute the most to the atomic mass of this atom?
a protons and electrons
b protons and neutrons
c neutrons and electrons
d electrons only

Explanation:

To determine which particles contribute most to atomic mass, we analyze the mass of each subatomic particle:

• Protons and neutrons have a mass of approximately 1 amu each.
• Electrons have a mass of about 0.0005 amu, which is negligible compared to protons and neutrons.

Thus, protons and neutrons (which are in the nucleus) contribute the most to the atomic mass, while electrons (with negligible mass) do not.

Answer:

B. Protons and neutrons