Question

Glucose when reduced with $HI$ and red phosphorus gives-
(A) n-hexane
(B) n-heptane
(C) n-pentane
(D) n-octane

Answer 1

Hint: Reducing agent is one in the reagents of an oxidation-reduction reaction that eliminates the other reagent by supplying electrons to the reagent. When, in a reaction, the reducing agent will not transfer electrons to another element, the reduction phase cannot occur.

Complete step by step solution:

During their pre-reaction conditions, the reducers have extra electrons (that is, they are reduced by themselves) whereas the oxidizers lose electrons (that is, they are oxidized by themselves). A reducing agent is usually located in one of the lowest possible oxidation states and is known as an electron donor. Types of reducing agents include earth metals, formic acid, oxalic acid and sulfite compounds.
Glucose is the source of energy for cell activity, and the control of its metabolism is of considerable significance. The starch molecules, the primary energy-reserve carbohydrate in plants, compose of thousands of linear glucose units. Cellulose, which is also circular, is another significant glucose product. Dextrose is a D-glucose molecule.
Red phosphorus is one of the most popular phosphorus allotropes and is known to be a ${P_4}$ molecule derivative. This occurs in an amorphous (non-crystalline) network of phosphorus atoms. It is also considered to be more stable than white phosphorus (another naturally occurring phosphorus allotrope). Red phosphorus will act as a strong reducing agent in the above reaction.
There are six carbons in the compound. After reacting with red phosphorus, the six carbons will be reduced to alkane.
$\Rightarrow CHO - {\left( {CHOH} \right)_4} - C{H_2}OH\xrightarrow{{HI/\operatorname{Re} dP}}n - Hexane \\\ \\\ \Rightarrow {C_6}{H_{12}}{O_6}\xrightarrow{{HI/\operatorname{Re} dP}}C{H_3}C{H_2}C{H_2}C{H_2}C{H_2}C{H_3} \\\$

Hence, it is clear that option A is the correct option.

Note: Glucose, also known as dextrose, is one of a group of carbohydrates known as simple sugars (monosaccharides). Glucose has the ${C_6}{H_{12}}{O_6}$ molecular formula. Glucose is primarily produced by plants and most algae through photosynthesis from water and carbon dioxide, utilizing sunlight energy, where it is used to create cellulose in cell walls, which is the most abundant carbohydrate.