Glucose in a waste stream is oxidised completely: C6H12O6 + 6O2 -> 6CO2 + 6H2O. Taking C = 12, H = 1, O = 16, the mass of oxygen needed to oxidise 18.0 g of glucose is:

JEE Main levelSingle correct optionDifficulty 2 of 3ev125

Glucose in a waste stream is oxidised completely: $C X_{6} H X_{12} O X_{6} + 6 O X_{2} 6 CO X_{2} + 6 H X_{2} O$ . Taking C = 12, H = 1, O = 16, the mass of oxygen needed to oxidise $18.0 g$ of glucose is:

Molar mass of glucose is 180 g/mol, so 18.0 g is 0.100 mol. It needs

6 \times 0.100 = 0.600

mol of

O X_{2}

, which is

0.600 \times 32 = 19.2

g. The value 26.4 g is the mass of

CO X_{2}

formed.