In a typical atom, which subatomic particle has the least mass?

• A. Proton
• B. Neutron
• C. Electron
• D. Alpha particle

Answer: (C)

Verified step by step guidance

1. Recall the three main subatomic particles found in an atom: protons, neutrons, and electrons.
2. Understand that protons and neutrons are located in the nucleus and have masses close to 1 atomic mass unit (amu) each.
3. Recognize that electrons orbit the nucleus and have a much smaller mass compared to protons and neutrons, approximately 1/1836 of a proton's mass.
4. Note that an alpha particle consists of 2 protons and 2 neutrons, so its mass is even greater than that of a single proton or neutron.
5. Conclude that among the listed options, the electron has the least mass.