The Element Rhenium (Re) Exists as Two Stable Isotopes and 18

question 50

Multiple Choice

The element rhenium (Re) exists as two stable isotopes and 18 unstable isotopes. Rhenium-185 has in its nucleus

• A) 75 protons, 110 neutrons.
• B) 75 protons, 75 neutrons.
• C) 75 protons, 130 neutrons.
• D) 130 protons, 75 neutrons.
• E) not enough information is given.

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Definitions:

Concentration Gradient

The gradual difference in the concentration of solutes in a solution between two regions.

Hair Receptors

Sensory nerve endings around hair follicles that allow the detection of light touch or fine movements over the skin.

Hearing And Balance

Sensory functions managed by the inner ear, where hearing involves the detection of sound waves and balance is maintained through the vestibular system.

Touch

The sense through which we perceive pressure, texture, and temperature, primarily using our skin.