The alpha particle carries two positive charges. Its mass is very nearly equal to that of
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UPSC Civil Services preparation
- Atwo protons
- Ban atom of heliumCorrect
- Csum of masses of two positrons and two neutrons
- Dtwo positrons as each positron carries a single positive charge
Explanation
An alpha particle is identical to the nucleus of a helium atom. It consists of two protons and two neutrons bound together. A complete helium atom consists of this same nucleus plus two orbiting electrons. Since the mass of electrons is negligible compared to the mass of protons and neutrons, the mass of an alpha particle is almost exactly equal to the mass of a helium atom. Therefore, option B is the most accurate description.
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