"Combustion Analysis" if there's carbon and hydrogen AND oxygen in the original molecule.
1. Get the number of moles of C and H from the masses of CO2 and H2O.
2. Convert them to MASS and the mass that's unaccounted for is the mass of oxygen.
3. Get the number of moles of oxygen from that.
4. Figure out what the relative ratio of each atom is
DONE.
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