Question

Free aldehyde group can be produced on hydrolysis of which of the following compound(s)?

• A. Maltose
• B. Sucrose
• C. $\alpha$-D Glucose
• D. Lactose

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A Maltose
B Sucrose
C $\alpha$-D Glucose
D Lactose

$\alpha$-D glucose has a cyclic hemiacetal structure. Hemiacetal on hydrolysis gives free aldehyde group.
Maltose, sucrose, and lactose are are disaccharides which on hydrolysis give monosaccharides in which the aldehyde group becomes free.
Maltose $\stackrel{\text{hydrolysis}}{\to }$ Glucose $+$ glucose.
Sucrose $\stackrel{\text{hydrolysis}}{\to }$ Glucose $+$ fructose.
Lactose $\stackrel{\text{hydrolysis}}{\to }$ Glucose $+$ galactose.