If 10²¹ molecules are removed from 200mg of CO₂, then the number of moles of CO₂ left are [IIT 1983]

Question: If 10²¹ molecules are removed from 200mg of CO₂, then the number of moles of CO₂ left are [IIT 1983]

(a) 2.85 10^-3

(b) 28.8 10^-3

(c) 0.288 10^-3

(d) 1.68 x 10^-2

Correct Answer: (a) 2.85 10^-3

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