Why are vitamin A and vitamin C essential to us ? Give their important sources.
Why are vitamin A and vitamin C essential to us ? Give their important sources.
Solution and Explanation
The deficiency of vitamin A leads to xerophthalmia (hardening of the cornea of the eye) and night blindness. The deficiency of vitamin C leads to scurvy (bleeding gums).
The sources of vitamin A are fish liver oil, carrots, butter, and milk. The sources of vitamin C are citrus fruits, amla, and green leafy vegetables.
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Write IUPAC names of the following compounds and classify them into primary, secondary and tertiary amines.
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Give one chemical test to distinguish between the following pairs of compounds.
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(ii) Secondary and tertiary amines
(iii) Ethylamine and aniline
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(v) Aniline and N-methylanilineAccount for the following:
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(ii) Ethylamine is soluble in water whereas aniline is not.
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(iv) Although amino group is o– and p– directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.
(v) Aniline does not undergo Friedel-Crafts reaction.
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Concepts Used:
Vitamins
Vitamins are natural and essential nutrients. In the growth and development of the human body it plays an important role. For proper growth, strong bones and good development needs the right quantity of vitamins in our body. These vitamins are organic substances that work in groups for the normal and smooth functioning of our body cells.
Types of Vitamins:
There are two main types of vitamins.
Fat-Soluble Vitamins-
Fat-soluble vitamins are stored in the fat cells. These vitamins require fat in order to be absorbed. Vitamin A, D, E and K are fat-soluble vitamins.
Water-Soluble Vitamins-
Water-soluble vitamins are not stored in our body because its excess gets excrete through the urine. Therefore, these vitamins need to be replenished constantly. Vitamin B and C are water-soluble vitamins.