Benzene, C6H6, reacts with oxygen, O2, to form CO2 and H2O. How much O2 is required for the complete combustion of 1.0 mol C6H6?

C6H6 + 02 forms CO2 + H20

Complete with factors to stabilize

C6H6 + 15/2 O2 forms 6 CO2 + 3 H2O

You take away only the info you need

C6H6 15/2 O2

1 mol 15/2 or 7,5 mol

15/2 or 7,5 mol of O2 are required.

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