In 1913, an Element Was Known to "Emanate" from Radium-226

question 66

Multiple Choice

In 1913, an element was known to "emanate" from radium-226 by alpha emission and then to decay to polonium-218, also by  emission. What was the unknown element?

• A) radon-222
• B) lead-214
• C) plutonium-238
• D) bismuth-214
• E) lead-218

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Definitions:

Willow Bark

The bark of certain willow tree species that contains salicin, a substance with pain-relieving and anti-inflammatory properties.

Echinacea

A genus of herbaceous plants, some species of which are used in herbal medicine, primarily for immune system support.

Melatonin

A substance secreted by the pineal gland that controls the circadian rhythms.

Melatonin

A hormone produced by the pineal gland that regulates sleep-wake cycles.