Mass of sucrose C12H22O11 produced by mixing 84 g of carbon, 12 g of hydrogen and 56 lit.O2 at 1atm and 273 K according to given reaction is
C(s)+H2+O2⟶C12H22O11
155.5
12C +11H2+112O2⟶C12H22O11
7 moles 6 moles 2.5moles
n2112 =n(C12H22O11)
2.5112 =n(C12H22O11)
n(C12H22O11) =511
n(C12H22O11) =511×342 =155.5gm