Radon is: select one: a. an alpha-emitting gas that penetrates the skin naturally. b. a naturally occurring gas produced during the radioactive decay of uranium. c. a metallic element produced in nuclear power plants. d. a secondary air pollutant resulting from photochemical smog. e. a by-product of nuclear energy production.

A

Explanation:

Radon is an alpha emitter. It emits alpha particles giving off gamma ray. It is a radioactive byproduct of radium-222.

Radon also penetrates the skin. This is because radon is a gas and chemically unreactive with most materials, it moves easily through very small spaces, such as those between particles of soil and rock, to the soil surface

Option B is wrong. It is produced during radioactive decay of radium and not uranium.

Option C is wrong. Radon is not a metallic element.

Option D is wrong also. It is not produced from photochemical smog

Option E is wrong. This is an extension of option B. Uranium is generally used in nuclear plant operations and not radium

no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.