Concept check—pick the wrong statement about basic nuclear/particle facts (only one statement below is incorrect). Which one is it?

Introduction / Context:
Many entry-level nuclear questions test whether you can separate accurate facts from plausible-sounding misconceptions. Electrons, positrons, protons, and alpha particles have well-established identities and masses that should be memorized for quick elimination logic in multiple-choice items.

Given Data / Assumptions:

• Protium (ordinary hydrogen) has a nucleus consisting of a single proton.
• β− radiation consists of high-energy electrons emitted in nuclear decay.
• The electron-to-proton mass ratio is roughly 1/1836 (≈ 1/1800 by rough GK).
• Positron has the same mass as an electron but positive charge.

Concept / Approach:
Evaluate each statement against standard constants and identities. A positron (e+) is the electron’s antiparticle; its mass is identical to the electron’s, far lighter than a proton. Therefore, any statement claiming a positron is heavier than a proton is false. The other statements align with standard definitions: β− equals an electron; protium’s nucleus is a proton; and the widely used rounded mass ratio is acceptable. An alpha particle is indeed a helium-4 nucleus (2p + 2n).

Step-by-Step Solution:
Check Statement A: true for 1H1 (protium).Check Statement B: β− is an electron → true.Check Statement C: 1/1800 is a rounded figure close to 1/1836 → acceptable.Check Statement D: positron mass = electron mass ≪ proton mass → false.Check Statement E: alpha = 2p + 2n → true.

Verification / Alternative check:
Reference mass values: m_e ≈ 9.11e−31 kg, m_p ≈ 1.67e−27 kg (≈ 1836 m_e). Positron mass equals m_e; therefore it cannot be heavier than a proton.

Why Other Options Are Wrong:
A/B/C/E are consistent with textbook definitions and accepted constants.D contradicts the equality m_e = m_positron and the much larger proton mass.

Common Pitfalls:
Mixing up “antiparticle” with “heavier partner”; antiparticles mirror charge and certain quantum numbers, not mass magnitude relative to the corresponding particle.

Final Answer:
A positron is heavier than a proton.