Qualitative Tests, Structure and Uses of Chloral hydrate, Hexamine

Chloral hydrate

Structure

Chloral hydrate is a solid, crystal-like substance of the formula C2H3Cl3O2. As a water-soluble and alcohol-soluble compound, chloral hydrate readily forms concentrated solutions. Chloral hydrate is said to be a hydrate of chloral (trichloroacetaldehyde); water can be added to chloral to obtain chloral hydrate. It is most commonly made by reacting chlorine with ethanol in an acidic solution. By chlorinating water with organic residues, the by-product is additionally formed.

Uses

As a sedative and hypnotic, chloral hydrate can also serve as a precursor for other chemicals. A key component of Hoyer's mounting medium (used for observing organisms through a microscope mounted on slides) and a clearing agent of chitin (and fibers) have also been found to be useful.

Qualitative tests

Carbonyl-containing organic compounds such as aldehydes and ketones are important. The structure of aldehyde is RCH(=O), whereas the structure of ketone is R2C(=O). An R group can take the form of an alkyl, an alkenyl, an alkynyl or an aryl.

Compounds with low molecular weights such as aldehydes and ketones are volatile. An aldehyde or ketone can be identified by two types of reactions, an addition reaction with a double bond, and an oxidation reaction. As mentioned, aldehydes consist of carbonyl groups attached to hydrogen atoms and to aromatic or aliphatic radicals. The carbonyl group of formaldehyde is attached to two hydrogen atoms, unlike most other organic compounds. Ketones contain two aliphatic or aromatic groups attached to the carbonyl group.

Hexamine

Structure

Traditionally, this medication is used to treat urinary tract infections, as its anti-infective properties make it effective against infections. As a result of hydrolysis at 0.2 molar pH, formaldehyde (CH2O) is slowly released into the environment, which has anti-infective properties. A white crystalline powder or white crystal of Methenamine is odourless, colourless, and hygroscopic.

Uses

• In the manufacture of phenolic resins, hexamine is used as a liquid or powder.
• Linings for clutches and brakes contain these binders.
• Treatment for excessive sweating and concomitant odor in the form of sprays and creams.
• Silver stain made from methenamine used in Grocott's stain.
• Solid fuel used as a heating source.
• It is used to preserve food.
• RDX is made with this as the primary ingredient.
• Vulcanized rubber is prevented by using this.
• Steel is protected against corrosion by this chemical.

Because the mandelic acid salt is used for treating urinary tract infections, its process of decomposition produces ammonia, and formaldehyde is bactericidal. Mandelic acid enhances this action of formaldehyde. Ammonium chloride or vitamin C (or ascorbic acid) are typically co-administered with ammonium chloride to maintain urinary acidity. Because of the adverse effects of this compound, namely chemically-induced hemorrhagic cystitis, its use had been temporarily reduced in the late 1990s. Presently, the use of this drug has been re-approved because more commonly used drugs have become resistant to antibiotics. Since the bacteria do not develop resistance to formaldehyde, this drug is ideal for long-term prophylactic treatment of urinary tract infections. Those suffering from chronic kidney disease should also avoid taking it. Sprays and creams containing hexamine are effective in the treatment of excessive sweating and concomitant odor.

Qualitative tests

Sodium bisulphate test

With 2,4-dinitrophenylhydrazine, aldehydes and ketones produce an orange to yellow precipitate.

Carbonyl groups can be detected in orange-yellow crystals.

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