Caffeine, a molecule found in coffee, tea, and certain soft drinks, contains C, H, O, and N. Combustion of 10.0 g of caffeine produces 18.13 g of CO₂, 4.639 g of H₂O, and 2.885 g of N₂. Determine the molar mass of the compound if it is between 150 and 210 g/mol.

194 g/mol.

Explanation:

Hello,

In this case, one first must compute the mass of each element as shown below:

Next, the corresponding moles:

Then, each element's subscripts is found to be:

Therefore, the empirical formula is:

Nonetheless, it has a molar mass of 97bg/mol, thereby, by multiplying such formula by 2 one gets:

Which has a molar mass of 194 g/mol being correctly contained in the given interval.

Best regards.