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JEE Advance - Chemistry (2016 - Paper 2 Offline - No. 13)

For "invert sugar", the correct statement(s) is(are)

(Given : specific rotations of (+)-sucrose, (+)-maltose, L-($$-$$)-glucose and L-(+)-fructose in aqueous solution are +66$$^\circ$$, +140$$^\circ$$, $$-$$52$$^\circ$$ and +92$$^\circ$$, respectively.)

"invert sugar" is prepared by acid catalyzed hydrolysis of maltose.
"invert sugar" is an equimolar mixture of D-(+)-glucose and D-($$-$$)-fructose.
specific rotation of "invert sugar" is $$-$$20$$^\circ$$.
on reaction with Br2 water, "invert sugar" forms saccharic acid as one of the products.

Explanation

Invert sugar is prepared by acid catalyzed hydrolysis of sucrose.

$${C_{12}}{H_{22}}{O_{11}} + {H_2}O\buildrel {HCl} \over \longrightarrow \underbrace {\mathop {{C_6}{H_{12}}{O_6}}\limits_{D - ( + ) - Glu\cos e} + \mathop {{C_6}{H_{12}}{O_6}}\limits_{D - ( - ) - Fructose} }_{Invert\,sugar}$$

Specific rotation of invert sugar is

[$$\alpha$$]mix = 0.5 $$\times$$ (+52) + 0.5 $$\times$$ ($$-$$92) = + 26 $$-$$ 46 = $$-$$20$$^\circ$$

On reaction with Br2 water, invert sugar forms gluconic acid as one of the products. Br2 water oxidises glucose into gluconic acid and fructose is not oxidised by it.

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