What volume of oxygen at STP is required to burn 500 dm^3 of ethene?

What volume of oxygen at STP is required to burn 500 dm^3 of ethene?

Explanation

ethene (C2H4)

C2H4 + O2 --------> CO2 + H20

balance the equation

 C2H4 + 3 O2 to 2 CO2 + 2 H2O

500 dm^3 of ethene x 3 

1500 dm^3