21.

How do you convert the following:

(i) C₆H₅CONH₂ to C₆H₅NH₂

(ii) Aniline to phenol

(iii) Ethanenitrile to ethanamine

Write the chemical equations involved when aniline is treated with the following reagents:

(i) Br₂ water
(ii) CHCI₃ + KOH
(iii) HCl

Write the names and structures of the monomers of the following polymers:
(i) Buna-S
(ii) Glyptal
(iii) Polyvinyl chloride

(i) Write the product obtained when D-glucose reacts with H₂N - OH.
(ii) Amino acids show amphoteric behaviour. Why?
(iii) Why cannot vitamin C be stored in our body?

Give reasons for the following:
(i) Phenol is more acidic than ethanol.
(ii) The boiling point of ethanol is higher in comparison to methoxymethane.
(iii) (CH₃)₃C - O - CH₃ on reaction with HI gives CH₃OH and (CH₃)₃C -I as the main products and not (CH₃)₃C -OH and CH₃I.

Seeing the growing cases of diabetes and depression among young children, Mr Lugani, the principal of on reputed school organised a seminar in which he invited parents and principals. They all resolved this issue by strictly banning junk food in schools and introducing healthy snacks and drinks like soup, lassi, milk, etc. in school canteens. They also decided to make compulsory half an hour of daily physical activities for the students in the morning assembly. After six months, Mr Lugani conducted the health survey is most of the schools and discovered a tremendous improvement in the health of the students.
After reading the above passage, answer the following questions:

(i) What are the values (at least two) displayed by Mr Lugani?
(ii) As a student, how can you spread awareness about this issue?
(iii) What are antidepressant drugs? Give an example.
(iv) Name the sweetening agent used in the preparation of sweets for a diabetic patient.

(a) Account for the following:

(i) Zr and Hf have almost similar atomic radii.

(ii) Transition metals show variable oxidation states. 

(iii) Cu+ ion is unstable in aqueous solution.

(b) Complete the following equations:

(i) 2 MnO₂ + 4 KOH + O₂--->

(ii) 2 Na₂CrO₄ + 2 H ⁺ -->

From the given data of E⁰ values answer the following Question:

(i) Which is strongest why is  value exceptionally positive?

(ii) Why is value highly negative as compared to other elements?

(iii) Reducing agent  Cr²⁺ or Fe²⁺? Give reason

(b) Why do actinoids show wide range f oxidation states? Write on the similarity between the chemistry of lanthanoids and actinoids.

 A compound 'A' of molecular formula C₂H₃OCl undergoes a series of reactions as shown below. Write the structures of A, B, C and D in the following reactions:

(b) Distinguish between the following:

(i) C₆H₅-COCH₃ and C₆H₅ - CHO

(ii) Benzoic acid and methyl benzoate

(c) Write the structure of 2- methylbutanal.