Identify correct conversion during acidic hydrolysis from the following :
(A) starch gives galactose.
(B) cane sugar gives equal amount of glucose and fructose.
(C) milk sugar gives glucose and galactose.
(D) amylopectin gives glucose and fructose.
(E) amylose gives only glucose.
Choose the correct answer from the options given below :

Solution

Chemistry ma’am · 3 steps

Know what each sugar is built from, and its hydrolysis products follow straight away.

1. Starch and its parts. Starch is a polymer of α-D-glucose only. Both of its components, amylose and amylopectin, give nothing but glucose on acidic hydrolysis.
2. The two disaccharides. Cane sugar (sucrose) is glucose joined to fructose, so it gives one mole of each, equal amounts. Milk sugar (lactose) is galactose joined to glucose, so it gives glucose and galactose.

   Statement	Sugar is made of	Correct?
   (A) starch gives galactose	glucose units only	No
   (B) cane sugar gives glucose and fructose equally	glucose + fructose	Yes
   (C) milk sugar gives glucose and galactose	glucose + galactose	Yes
   (D) amylopectin gives glucose and fructose	glucose units only	No
   (E) amylose gives only glucose	glucose units only	Yes

3. So. The correct statements are (B), (C) and (E), which is option (c).

The idea to keep. Starch, amylose, amylopectin, glycogen and cellulose all hydrolyse to glucose alone. Sucrose gives glucose + fructose, lactose gives glucose + galactose, and maltose gives two glucose.

Answer from the NTA final answer key. Solution by PrepWiser.