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New answer posted
9 months agoContributor-Level 10
This is a Short Type Questions as classified in NCERT Exemplar
Ans:
Direct nitration of aniline is not possible on account of oxidation of -NH2 group. However, nitration can be carried after protecting the -NH2 group by acetylation to give acetanilide which is then nitrated and finally hydrolysed to give o- and p-nitroanilines.
The acetyl group being electron withdrawing attracts the lone pair of electrons of the N-atom towards carbonyl group.
As a result, the activating effect -NH2 group is reduced i.e., the lone pair of electrons on nitrogen is less available for donation to benzene ring by resonance. Therefore, acti
New answer posted
9 months agoContributor-Level 10
This is a Short Answer Type Questions as classified in NCERT Exemplar
Lactose sugar is a naturally occurring sugar found in milk. D galactose and D glucose, two monosaccharide molecules, are linked together. As a result, disaccharides are the name given to these oligosaccharides.
New answer posted
9 months agoContributor-Level 10
This is a multiple choice answer as classified in NCERT Exemplar
(a, b, c)
(a) Iproniazid is a hydrazine drug used as an antidepressant.
(b) Phenelzine is also known as Nardil. It is used in the treatment of major depressive disorder.
(c) Equanil is used in controlling depression and hypertension.
(d) Salvarsan is an antibacterial drug. It is used in the treatment of Syphilis.
New answer posted
9 months agoContributor-Level 10
This is a Short Type Questions as classified in NCERT Exemplar
Ans: HNO3 acts as a base in the nitrating mixture (HNO3 + H2SO4) and provides the electrophile.
New answer posted
9 months agoContributor-Level 10
This is a multiple choice answer as classified in NCERT Exemplar
(a, b)
(a) Sulphapyridine is a sulphonamide antibacterial drug.
(b) Prontosil is also called sulphamidochrysoidine.
(c) Salvarsan is arsenic based antibacterial drug.
(d) Nardil is an antidepressant drug.
New answer posted
9 months agoContributor-Level 10
This is a multiple choice answer as classified in NCERT Exemplar
(a, b) Barbiturates are tranquilizers which are used as hypnotics or sleep inducing agents.
New answer posted
9 months agoContributor-Level 10
This is a multiple choice answer as classified in NCERT Exemplar
(b, c)
(a) CHCl3 (chloroform) was used as an anaesthesia in surgery but now it is used in the production of the Freon refrigerant R-22.
(b) Iodoform (CFH3) produces iodine on coming in contact with skin, so it is used as an antiseptic for wounds.
(c) Boric acid (IT3BO3) in dilute aqueous solution is a weak antiseptic for eyes. Thus, chemical messenger gives message to the all without entering the cell.
(d) Chlorine in the concentration of 0.2 of 0.4 ppm in aqueous solution and sulphur dioxide in very low concentrations, are disinfectants.
New answer posted
9 months agoContributor-Level 10
This is a Multiple Choice Questions as classified in NCERT Exemplar
Ans: Option (A and B)
Benzene diazonium chloride reacts with phenol to form p-hydroxy azobenzene by coupling the phenol molecule at its para position with the diazonium salt. This is referred to as a coupling reaction. This is an illustration of an electrophilic substitution reaction.
At room temperature, aniline reacts with bromine water to form a white precipitate of 2,4,6-tribromoaniline.
By acetylation with acetic anhydride to protect the −NH2 group, then carrying out the desired substitution followed by hydrolysis of the substituted amide to the substi
New answer posted
9 months agoContributor-Level 10
This is a Multiple Answer Type Questions as classified in NCERT Exemplar
Correct options are a and d.
Enzymes are protein molecules that operate as biocatalysts in the body, facilitating chemical processes. The pace of the reaction is accelerated by these catalysts.
New answer posted
9 months agoContributor-Level 10
This is a Multiple Choice Questions as classified in NCERT Exemplar
Ans: a and b
In addition to the nitro derivatives, direct nitration of aniline produces tarry oxidation products. Furthermore, aniline is protonated in the strongly acidic medium to form the anilinium ion, which is meta directing. As a result, in addition to the ortho and para derivatives, a significant amount of meta derivative is formed.
However, by protecting the? NH2 group with an acetylation reaction with acetic anhydride, the nitration reaction can be controlled and the p-nitro derivative obtained as the main product.
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