Question

Concentrated nitric acid oxidizes cane sugar to
A) $C{{O}_{2}} \,and \,{{H}_{2}}O$
B) $CO \,and\, {{H}_{2}}O$
C) $CO,C{{O}_{2}}\,and \,{{H}_{2}}O$
D) Oxalic acid and water

Answer 1

Sucrose is commonly referred to as cane sugar or table sugar. It is composed of two monosaccharide units called glucose and fructose. It is known as a non reducing disaccharide which has the chemical formula ${{C}_{12}}{{H}_{22}}{{O}_{11}}$. In sucrose glycosidic linkage is present which connects the two carbohydrate groups.

Complete solution:
The structure of sucrose is monoclinic in nature which is soluble in water and has a sweet taste. There is no presence of anomeric hydroxyl group in the molecule of sucrose. Due to this reason it has been classified as non reducing sugar as it does not act as a reducing agent. In the reaction where sucrose is treated with concentrated nitric acid, the concentrated nitric acid acts as an oxidizing agent in the reaction. The reaction is the following:
${{C}_{12}}{{H}_{22}}{{O}_{11}}\xrightarrow[HN{{O}_{3}}]{conc}HOOC-COOH+{{H}_{2}}O$
The HOOC-COOH is referred to as oxalic acid. So the products formed are oxalic acid and water. The correct option is option ‘d’.
The concentrated nitric acid is acted as an oxidising agent because when it undergoes decomposition it yields a nascent oxygen which is highly reactive and it has the ability to oxidise metals and non metals and organic and inorganic compounds.

Note: Oxalic acid is considered as a dicarboxylic acid or Ethanedioic acid or oxalic acid. This acid is found in vegetables and plants. It is a white crystalline solid which has the ability to be colourless when dissolved in water. It has the structure of two polymorphs. It is also used as a chelating agent with oxalate as its conjugate base.