Concept: The mass of subatomic particles is a fundamental constant. Protons and neutrons make up almost all the mass of an atom, while electrons are comparatively negligible.
Formula: $$ m_p \approx 1836 \times m_e $$
Solution: - The rest mass of a proton is \( 1.672 \times 10^{-27} \text{ kg} \).
- The rest mass of an electron is \( 9.109 \times 10^{-31} \text{ kg} \).
- Dividing the mass of the proton by the mass of the electron gives a ratio of approximately 1836.
- This means you would need about 1836 electrons to equal the mass of a single proton.
Why other options are incorrect: A positron is the antimatter equivalent of an electron, so it has the same tiny mass as an electron. Protons and neutrons have nearly identical masses, so a proton is definitely not equal to 1836 neutrons.
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