Question

Given below are two statements: 
Statement I: D-(+)-glucose + D-(+)-fructose $\xrightarrow{H_2O}$ sucrose sucrose $\xrightarrow{\text{Hydrolysis}}$ D-(+)-glucose + D-(+)-fructose
Statement II: Invert sugar is formed during sucrose hydrolysis. 
In the light of the above statements, choose the correct answer from the options given below -

• A. Both Statement I and Statement II are true.
• B. Statement I is false but Statement II is true.
• C. Statement I is true but Statement II is false.
• D. Both Statement I and Statement II are false.

Hint:

In biochemical processes, the hydrolysis of sucrose results in the formation of invert sugar (a mixture of glucose and fructose), but the synthesis of sucrose is the reverse reaction of this process.

Answer 1

The Correct Option is B

To address the given statements regarding the chemistry of sugars:

1. Statement I Explanation:
   • The statement "D-(+)-glucose + D-(+)-fructose $\xrightarrow{H_2O}$ sucrose sucrose $\xrightarrow{\text{Hydrolysis}}$ D-(+)-glucose + D-(+)-fructose" is incorrect.
   • In reality, D-(+)-glucose and D-(+)-fructose combine through a condensation reaction (not simply in the presence of water) to form sucrose. This is a dehydration reaction as it removes a molecule of water, hence $\xrightarrow{H_2O}$ is incorrect for synthesis. Conversely, hydrolysis of sucrose involves breaking it down to D-(+)-glucose and D-(+)-fructose in the presence of water.
2. Statement II Explanation:
   • Sucrose hydrolysis indeed produces invert sugar, a mixture of D-(+)-glucose and D-(-)-fructose. This mixture is termed 'invert sugar' because fructose has a greater optical rotation than glucose, causing a change (inversion) in the direction of rotation of plane-polarized light compared to that by sucrose.

Therefore, after evaluating the statements, we can conclude:

• Statement I is false as it incorrectly describes the reaction process involving sucrose.
• Statement II is true, as it correctly states that invert sugar forms as a product of sucrose hydrolysis.

Thus, the correct answer is: Statement I is false but Statement II is true.

Answer 2

Step 1: Understanding Statement I
Statement I is incorrect. The reaction described in Statement I is wrong because it says that D-(+)-glucose and D-(+)-fructose combine to form sucrose, which is incorrect. The correct reaction should be the formation of sucrose from glucose and fructose, not the other way around.
Therefore, Statement I is false because it incorrectly describes the formation of sucrose.
Step 2: Understanding Statement II
Statement II is correct. Invert sugar is indeed formed during the hydrolysis of sucrose. When sucrose undergoes hydrolysis (by the action of water), it breaks down into glucose and fructose. This mixture of glucose and fructose is called invert sugar.
Therefore, Statement II is true because invert sugar is indeed formed during sucrose hydrolysis.
Step 3: Conclusion
Statement I is false because it incorrectly describes the synthesis of sucrose.
Statement II is true because it correctly describes the formation of invert sugar during sucrose hydrolysis.