Question

C6H12O6(s) + 9 O2(g) --------- 6 CO2(g) + 6 H2O(g) What volume of oxygen gas measured at 27oC and 0.987 atm is needed to react with 8 g of C6H12O6? (C-12.01, H-1.008, O-16.00).

Answer 1

First, your equation isn't balanced. Balance it.
mols C6H12O6 = grams/molar mass = ?
Using the coefficients in the balanced equation convert mols C6H12O6 to mols O2.
Then use PV = nRT and convert mols O2 to volume in L at the conditions listed.