40.7% Carbon, 54.2% Oxygen, 5.10% Hydrogen
Molar mass is 180g/mol.
What is the formula?
If we assume we've got 100 grams of the substance, then we'd have 40.7 g C, right?
How many moles is that?
(40.7 g)(1 mol/12 g) = 3.39 mol
In 100 g, we'd have 54.2 g oxygen, right? How many moles is that?
(54.2 g)(1 mol/16 g) = ...
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