A sugar ‘X’ dehydrates very slowly under acidic conditions to give furfural which on further reaction with resorcinol gives the coloured product after some time. Sugar ‘X’ is
- Aldopentose
- Aldotetrose
- Oxalic acid
- Ketotetrose
The Correct Option is A
Solution and Explanation
The correct answer is (A):
This is based on Seliwamoff’s test, which is used to distinguish between aldoses and Kotoses. Ketoses give this test more rapidly than aldoses because they are more rapidly dehydrated than aldoses.
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Concepts Used:
Biomolecules
Biomolecules are the most essential organic molecules, which are involved in the maintenance and metabolic processes of living organisms. These non-living molecules are the actual foot-soldiers of the battle of sustenance of life.
There are four major classes of Biomolecules – Carbohydrates, Proteins, Nucleic acids and Lipids.
- Carbohydrates are chemically defined as polyhydroxy aldehydes or ketones or compounds which produce them on hydrolysis.
- Proteins are another class of indispensable biomolecules, which make up around 50per cent of the cellular dry weight. Proteins are polymers of amino acids arranged in the form of polypeptide chains. The structure of proteins is classified as primary, secondary, tertiary and quaternary in some cases.
- Nucleic acids refer to the genetic material found in the cell that carries all the hereditary information from parents to progeny. There are two types of nucleic acids namely, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The main function of nucleic acid is the transfer of genetic information and synthesis of proteins by processes known as translation and transcription.
- Lipids are organic substances that are insoluble in water, soluble in organic solvents, are related to fatty acids and are utilized by the living cell.