The balanced equation for combustion in an acetylene torch is shown below: 2 upper C subscript 2 upper H subscript 2 plus 5 upper O subscript 2 right arrow 4 upper C upper o subscript 2 plus 2 upper H subscript 2 upper O. The acetylene tank contains 35.0 mol C2H2, and the oxygen tank contains 84.0 mol O2. How many moles of O2 are needed to react completely with 35.0 mol C2H2? mol O2

87.5 mol of O2 is required to completely react with 35.0mol of C2H2

Explanation:

The equation is given as;

2C2H2 + 5O2 --> 4CO2  +  2H2O

The acetylene tank contains 35.0 mol C2H2, and the oxygen tank contains 84.0 mol O2.

From the balanced equatioon, the realtionship between the reactants is given as;

2 mol of C2H2 reacts with 5 mol of O2

How many mol of O2 would then react with C2H2?

2 mol C2H2 = 5 mol O2

35 mol C2H2 = x mol O2

Upon solving for x;

x = 35 * 5 / 2

x = 87.5 mol of O2