An Element Found in Another Galaxy Exists as Two Isotopes

question 63

Multiple Choice

An element found in another galaxy exists as two isotopes. If 80.0 percent of the atoms have an atomic mass of 80.00 amu and the other 20.0 percent have an atomic mass of 82.00 amu, what is the atomic mass of the element?

• A)81.0 amu
• B)64.0 amu
• C)80.4 amu
• D)16.4 amu
• E)81.6 amu

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Definitions:

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A complete classification system for mental disorders, the Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders is employed by medical professionals.

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Unpleasant, sometimes dangerous reactions that may occur when people who use a drug regularly stop taking or reduce their dosage of the drug.

Tolerance

The adjustment that the brain and the body make to the regular use of certain drugs so that ever larger doses are needed to achieve the earlier effects.