The Element X Has Three Naturally Occurring Isotopes

question 185

Multiple Choice

The element X has three naturally occurring isotopes. The isotopic masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is ________ amu.

• A)161.75
• B)162.03
• C)162.35
• D)163.15
• E)33.33

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Definitions:

Periods

Distinct spans of time marked by specific events, conditions, or characteristics.

REM Sleep

A phase of sleep characterized by rapid eye movements, increased brain activity, and vivid dreams.

NREM Sleep

Non-Rapid Eye Movement sleep, a restorative sleep phase that includes stages 1 through 3, each deeper than the last.

Cycles

Sequences of events that repeat in a regular and predictable manner, such as the water cycle or menstrual cycle.