Chem Majors! PLEASE HELP! Consider the equation for the combustion of butane..

I cant figure this one out for my cats life :(

Consider the equation for the combustion of butane:

2 C4H10(g) + 13 O2(g) 8 CO2(g) + 10 H2O(g)

What volume of oxygen at STP would be needed to completely react with 50.0 g of butane?

Convert 50g of butane to moles of butane by dividing by the atomic weight of butane.

Convert from moles of butane to moles of equations by dividing by 2.

Convert from moles of equations to moles of oxygen by multiplying by 13.

Convert from moles of oxygen to volume of oxygen by multiplying by 22.4L. Remember that number. You'll need it a lot.

C4H10 = 58.14 g/mol

Using Dimensional Analysis, you ahve:
50.0g C4H10 * 1 mol C4H10 / 58.14g C4H10 * 13 mol O2 / 2 mol C4H10 *22.4L O2/mol O2 = 125.2 L