Question

Write only equations for the reactions for preparation of glucose from sugar and starch.

Answer 1

We need to know that the basic functional unit of carbohydrates is $C{H_2}O$. It is a combination of carbon and water. The monomer unit of carbohydrate is ${\text{C}}{{\text{H}}_{\text{2}}}{\text{O}}$. Carbon and water are the basic units of carbohydrates. The word meaning of carbohydrate is ${\text{carbon + hydrate}}$. Hydrate means nothing but water. Carbohydrates are also known as saccharides. The word meaning of saccharides is sugar. Glucose is a well known and simplest example for carbohydrates. The chemical formula of glucose is${{\text{C}}_{\text{6}}}{{\text{H}}_{{\text{12}}}}{{\text{O}}_{\text{6}}}$. The simplest representation of a glucose molecule is ${{\text{(C}}{{\text{H}}_{\text{2}}}{\text{O)}}_6}$.

Complete answer:
We need to remember that the sugar is extracted from sugar cane. The chemical formula of sugar is sucrose. The molecular formula of sucrose is ${C_{12}}{H_{22}}{O_{11}}$.
The hydrolysis of sucrose to give the product of glucose and fructose. The glucose and fructose have the same molecular formula. But the functional group wise both are different.
The chemical reaction for the above discussion is given below,
${C_{12}}{H_{22}}{O_{11}} + {H_2}O \to {C_6}{H_{12}}{O_6} + {C_6}{H_{12}}{O_6}$
The hydrolysis of starch is also given the product of glucose. The molecular formula of starch is${({C_6}{H_{10}}{O_5})_n}$.
The chemical reaction for the above discussion is given below,
${({C_6}{H_{10}}{O_5})_n} + n{H_2}O \to n({C_6}{H_{12}}{O_6})$
According to the above discussion, we get an equation for the reactions for preparation of glucose from sugar and starch.

Additional information:
Carbohydrates are classified as three major groups. This classification is based on the hydrolysis of carbohydrates. There are monosaccharides, oligosaccharides and polysaccharides. Monosaccharides here means only one carboxylic group in the molecule. Respect that carboxylic group hydrolysis will happen. Glucose, fructose are examples of monosaccharides. Lactose and maltose are examples of oligosaccharides, because they contain more than one functional monomer in the structure. Starch, glycogen and cellulose are the examples of polysaccharides because they have more than three monomers in the structure.

Note:
We have to know that carbohydrates are classified as two types. This classification is based on the functional monomer in the carbohydrates. In carbohydrates aldehyde and ketone act as monomers. According to that, carbohydrates are separated as aldose and ketose.
In carbohydrates also classified as many types depending on the number of the carbon atom. Depending on the value of n $(3,4,5,6,...)$are classified as (trioses, tetroses, pentoses, hexoses etc…).