The number of moles of O2 that are needed to react completely with 35.0 mol C2H2 is; 87.5 mol of O2
We are given The equation for combustion in an acetylene torch as;
2C2H2 + 5O2 --> 4CO2 + 2H2O
We are given;
From the balanced equation above, we can see that;
2 mol of C2H2 reacts with 5 mol of O2
Thus, by proportion;
If 2 mol C2H2 = 5 mol O2
Then;
35 mol C2H2 = 35 mol C2H2 × 5 mol O2/2 mol C2H2
>> 87.5 mol of O2
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