Physics Question

Question

How many moles of caffeine are there in 312.0g of caffeine?

Answer 1

First, you must look up the formula for caffeine: C₈H₁₀N₄O₂.

Next, use the periodic table to calculate the molar mass of caffeine.

Then, use the molar mass as a conversion factor to calculate the number of moles of caffeine in 312.0g.

 

312.0 g caffeine × (1 mol caffeine / 194.19 g caffeine) = # mol caffeine

 

You can cancel the "g caffeine" units since they are reciprocals, then simply divide 312.0/194.19 to yield the # mol caffeine.