Which subatomic particles primarily affect the stability of an atom?

• A. Electrons
• B. Neutrons
• C. Protons
• D. Quarks

Answer: (B)

Verified step by step guidance

1. Understand that an atom consists of three main subatomic particles: protons, neutrons, and electrons.
2. Recall that protons determine the identity of the element (its atomic number) and electrons determine chemical behavior, but neither primarily controls stability.
3. Recognize that neutrons contribute to the nucleus's stability by offsetting the repulsive forces between positively charged protons.
4. Learn that too few or too many neutrons compared to protons can make the nucleus unstable, leading to radioactive decay.
5. Conclude that neutrons are the subatomic particles that primarily affect the stability of an atom.