How Many Atoms of Rubidium-85 Are in 87

question 32

Multiple Choice

How many atoms of rubidium-85 are in 87.2 g of rubidium? Rubidium-85 is 72.2 % abundant.

• A) 5.16 × 10⁴⁶ atoms
• B) 4.44 × 10²³ atoms
• C) 8.51 × 10²³ atoms
• D) 6.14 × 10²² atoms
• E) 1.02 × 10²⁴ atoms

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