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Question
Deduce the number of molecules of the following compound in the given quantity.
8.8g carbon dioxide
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Solution
Number of moles in CO2 = `("Mass of CO"_2" in grams")/"Molecular mass of CO"_2`
= `8.8/44`
= 0.2 mole
∴ 0.2 moles of CO2 contains = 0.2 × 6.022 × 1023 molecules = 1.2044 × 1023 molecules.
∴ The number of molecules in 8.8 grams of carbon dioxide is 1.2044 × 1023.
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