Benzene reacts with O₂ to produce CO₂ and H₂O, i.e.
C₆H₆ + 7.5 O₂ → 6 CO₂ + 3 H₂O
According to equation,
78.11 g (1 mole) C₆H₆ reacts to produce = 264 g (6 moles) of CO₂
Hence,
7.80 g C₆H₆ when reacted will produce = X g of CO₂
Solving for X,
X = (7.80 g × 264 g) ÷ 78.11 g
X = 26.36 g of CO₂
Theoretical Yield:
26.36 g of CO₂ produced is theoretical yield which shows 100% reaction between benzene and oxygen.
Actual Yield:
According to statement the actual amount of CO₂ produced is 3.0 g of CO₂.
%age Yield:
%age Yield = (Actual Yield ÷ Theoretical Yield) × 100
Putting Values,
%age Yield = (3.00 g ÷ 26.36 g) × 100
%age Yield = 11.38 %