Chlorine has two naturally occurring isotopes: chlorine-35 and chlorine-37. The relative atomic mass of chlorine is 35.5. What does this value indicate about the natural abundance of these isotopes?

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Question

Chlorine has two naturally occurring isotopes: chlorine-35 and chlorine-37. The relative atomic mass of chlorine is 35.5. What does this value indicate about the natural abundance of these isotopes?

Accepted Answer

Chlorine-35 is more abundant than chlorine-37 — Award 1 mark for deducing that chlorine-35 is more abundant because the relative atomic mass (35.5) is closer to 35 than to 37. A is incorrect — equal amounts would give Ar = 36. C is incorrect — if chlorine-37 were more abundant, Ar would be closer to 37. D is incorrect — the existence of Ar = 35.5 proves both isotopes exist.

Answer

Chlorine-35 is more abundant than chlorine-37

Answer

Only chlorine-35 exists naturally

Answer

Chlorine-35 and chlorine-37 are present in equal amounts

Answer

Chlorine-37 is more abundant than chlorine-35

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