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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ev162

A waste water contains $90 mg L^{- 1}$ of glucose (C = 12, H = 1, O = 16), oxidised by $C X_{6} H X_{12} O X_{6} + 6 O X_{2} 6 CO X_{2} + 6 H X_{2} O$ . Select the correct statements.

AThe theoretical oxygen demand is $96 mg L^{- 1}$
BThe theoretical oxygen demand is $48 mg L^{- 1}$
CThe mass of $CO X_{2}$ formed is $132 mg L^{- 1}$
DThe mass of $CO X_{2}$ formed is $66 mg L^{- 1}$

Answer: A, C

90 mg/L of glucose is

0.5

mmol/L. It needs

0.5 \times 6 \times 32 = 96

mg/L of

O X_{2}

and forms

0.5 \times 6 \times 44 = 132

mg/L of

CO X_{2}

. The values 48 and 66 correspond to using 3 mol of

O X_{2}

and 3 mol of

CO X_{2}

per mole of glucose.

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