Rubidium Has Two Naturally Occurring Isotopes,⁸⁵Rb (84

question 3

Multiple Choice

Rubidium has two naturally occurring isotopes,⁸⁵Rb (84.912 amu) and ⁸⁷Rb (86.909 amu) .Rubidium-85 is the more abundant isotope (72.17%) .Calculate the average atomic mass of Rb.

• A)86.91 amu
• B)85.47 amu
• C)85.91 amu
• D)86.35 amu
• E)86.00 amu

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Definitions:

Assimilation

The process of absorbing and integrating new information into existing knowledge.

Denitrifying Bacteria

Microorganisms that convert nitrates in the soil to nitrogen gas, playing a vital role in the nitrogen cycle.

Atmospheric Nitrogen

A component of the Earth's atmosphere, making up about 78% by volume, primarily in the form of nitrogen gas (N2).

Organic Nitrogen Compounds

Chemical compounds that contain carbon and nitrogen, playing various roles in the metabolism of living organisms.