Write the reactions of (i) aromatic and (ii) aliphatic primary amines with nitrous acid
Solution and Explanation
(i) Aromatic amines react with nitrous acid (prepared in situ from NaNO2 and a mineral acid such as HCl) at 273 - 278 K to form stable aromatic diazonium salts i.e., NaCl and H2O.
(ii) Aliphatic primary amines react with nitrous acid (prepared in situ from NaNO2 and a mineral acid such as HCl) to form unstable aliphatic diazonium salts, which further produce alcohol and HCl with the evolution of N2 gas.
Top Questions on Amines
- The best reagent for converting propanamide into propanamine is:
- Give plausible explanation for the following: (a) Diazonium salts of aromatic amines are stable.
(b) Aniline does not undergo Friedel–Crafts reaction.
(c) Aniline on nitration gives a substantial amount of meta product. - Assertion (A): Acetamide (structure: \(\text{C}_6\text{H}_5\text{NHCOCH}_3\)) is less basic than aniline.
Reason (R): Acetylation of aniline results in decrease of electron density on nitrogen. - The chemical test which can be used to distinguish between ethanamine and aniline is:
- If amines are arranged in increasing order of their basic strength in gaseous phase, the correct order will be:
Questions Asked in CBSE CLASS XII exam
- The firm of Amish, Nitish and Misha, who have been sharing profits in the ratio of 2 : 2 : 1, have existed for some years. Misha wanted that she should get equal share in the profits with Amish and Nitish and she further wished that the change in the profit sharing ratio should come into effect retrospectively for the last three years. Amish and Nitish had agreement for this.
The profits for the last three years were: 2021–22 ₹ 1,15,000; 2022–23 ₹ 1,24,000; 2023–24 ₹ 2,11,000
Show adjustment of profits by means of a single adjustment journal entry. Show your working clearly.- CBSE CLASS XII - 2025
- Profit sharing ratio
- List two reasons that make copper releasing IUDs as effective contraceptives.
- CBSE CLASS XII - 2025
- Reproductive Health – Problems And Strategies
A carpenter needs to make a wooden cuboidal box, closed from all sides, which has a square base and fixed volume. Since he is short of the paint required to paint the box on completion, he wants the surface area to be minimum.
On the basis of the above information, answer the following questions :
Find \( \frac{dS}{dx} \).- CBSE CLASS XII - 2025
- Differentiation
- Zaina, Yash and Kiran were partners in a firm sharing profits and losses in the ratio of 2 : 2 : 1. Zaina died on 1st July, 2024. As per the partnership deed, Zaina’s share of profit or loss till the date of her death was to be calculated on the basis of sales. Sales for the year ended 31st March, 2024 amounted to ₹ 4,00,000 and that from 1st April to 30th June, 2024 was ₹ 1,50,000. The profit for the year ending 31st March, 2024 was ₹ 1,00,000. Calculate Zaina’s share of profit in the firm till the date of her death and pass necessary journal entry for the same.
- CBSE CLASS XII - 2025
- Retirement and Death of a Partner
- Alok, Sameer and Tushar were partners in a firm sharing profits and losses in the ratio of 4 : 3 : 2. With effect from 1st April, 2024, they decided to share future profits and losses in the ratio of 3 : 2 : 4. Their Balance Sheet as at 31st March, 2024 showed the following: (i) Advertisement Suspense Account \u20b9 90,000.
(ii) Credit Balance of \u20b9 2,70,000 in Profit and Loss Account.
Goodwill of the firm was valued at \u20b9 4,50,000 and revaluation of assets and liabilities resulted in a loss of \u20b9 1,80,000. Partners did not want to distribute the amount of Advertisement Suspense Account and the Profit and Loss Account. They also decided that revalued values of assets and liabilities were not to be recorded in the books. Pass a single adjustment entry to give effect to the above. Also show your workings clearly.- CBSE CLASS XII - 2025
- Admission of a Partner
Concepts Used:
Amines - Chemical Properties
There are many chemical properties of amines.
The primary and secondary amines, including several amine derivatives, have a direct impact on their properties due to the presence of hydrogen bonding. The compounds containing phosphorus have a lower boiling point and the compounds containing amines and alcohol have a higher boiling point. The structure of alkanols is immensely similar to that of amine except the presence of the hydroxyl group. In such a case, oxygen has a higher electronegativity than that of nitrogen, so alkanol compounds are more acidic in nature in comparison to the amines.
On account of the ability to form hydrogen bonds, the amines have tendencies of high solubility in water. The amine molecules such as Ethyl, diethyl, triethyl, and Methyl are gaseous in nature. Whereas, higher weight amines have a solid structure and alkyl amines have a liquid structure. There is an ammonia smell to gaseous amines and a fishy smell to liquid amines. The solubility of amines entirely depends upon the number of carbon atoms in the molecule.