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How many grams of caffeine are found in 6.500 x 10^22 molecules of caffeine?

User AndyG
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1 Answer

13 votes

Answer:

21.614 grams are found in
6.5 * 10^(22) molecules of caffeine.

Step-by-step explanation:

The chemical formula for caffeine is
C_(8)H_(10)N_(4)O_(2), the molar weight of caffeine is:


M = 8\cdot \left(12.011\,(g)/(mol) \right) + 16\cdot \left(1.008\,(g)/(mol) \right)+4\cdot \left(14.007\,(g)/(mol) \right)+2\cdot \left(15.999\,(g)/(mol) \right)


M = 200.242\,(g)/(mol)

According to Avogadro's Law, a mol of caffeine contains
6.022* 10^(23) molecules. The number of grams contained in
6.5 * 10^(22) molecules is determined by simple rule of three:


x = (6.5* 10^(22)\,molecules)/(6.022* 10^(23)\,molecules) * 200.242\,g


x = 21.614\,g

21.614 grams are found in
6.5 * 10^(22) molecules of caffeine.

User Anisia
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