2C2H2+ 5O2-> 4CO2+ 2H20. If 1 mole of C2H2 reacts with oxygen, how many moles of C02 are produced.

Doesn't it indicate twice (4/2) as much?

To find out how many moles of CO2 are produced when 1 mole of C2H2 reacts with oxygen, you need to use the stoichiometric coefficients from the balanced chemical equation.

From the balanced chemical equation:
2C2H2 + 5O2 -> 4CO2 + 2H2O

We can see that 2 moles of C2H2 react with 5 moles of O2 to produce 4 moles of CO2.

So, if 2 moles of C2H2 react, we can find out how many moles of CO2 are produced by setting up a ratio:

2 moles of C2H2: 4 moles of CO2

Since we have 1 mole of C2H2, we can use the ratio to find out the number of moles of CO2:

(1 mole of C2H2) * (4 moles of CO2 / 2 moles of C2H2) = 2 moles of CO2

Therefore, when 1 mole of C2H2 reacts with oxygen, 2 moles of CO2 are produced.