Problem: Determine the empirical and molecular formulas of each of the following substances. For example, butane has an empirical formula of C2H5 (lowest whole-number ratio) and a molecular formula of C4H10, where the molecular formula corresponds to the molar mass of 58.12 g/mol.Ibuprofen, a headache remedy, contains 75.69% C, 8.80%  H, and 15.51%  O by mass and has a molar mass of 206 g/mol.

FREE Expert Solution

Step 1: We are given 75.69% C, 8.80%  H, and 15.51% O by mass. 


% mass=mass of Xtotal mass×100


Assuming we have 100 g of the compound, this means we have 75.69 g C, 8.80 g H, and 15.51 g O.


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Problem Details

Determine the empirical and molecular formulas of each of the following substances. For example, butane has an empirical formula of C2H5 (lowest whole-number ratio) and a molecular formula of C4H10, where the molecular formula corresponds to the molar mass of 58.12 g/mol.

Ibuprofen, a headache remedy, contains 75.69% C, 8.80%  H, and 15.51%  O by mass and has a molar mass of 206 g/mol.

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Based on our data, we think this problem is relevant for Professor Bursten's class at Worcester Polytechnic Institute.