Seeing the growing cases of diabetes and depression among young children, Mr. Chopra, the principal of one reputed school organized 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. Chopra conducted the health survey in 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. Chopra? (ii) As a student, how can you spread awareness about this issue? (iii) Why should antidepressant drugs not be taken without consulting a doctor? (iv) Give two examples of artificial sweeteners.

(a) Account for the following:

(i) Cu⁺ is unstable in an aqueous solution.

(ii) Transition metals form complex compounds.

(b) Complete the following equation:

Cr₂O₇^2- + 8H⁺ + 3NO₂^- →

Write the names and structures of the monomers of the following polymers:

(i) Terylene

(ii) Buna-S

(iii) Neoprene

(a) Account for the following:

(i) Acidic character increases from HF to HI.

(ii) There is a large difference between the melting and boiling points of oxygen and sulphur.

(iii) Nitrogen does not form pentahalide.

(b) Draw the structures of the following:

(i) ClF₃ (ii) XeF₄

OR

(i) Which allotrope of phosphorus is reactive and why?

(ii) How are the supersonic jet aeroplanes responsible for the depletion of ozone layer?

(iii) F₂ has lower bond dissociation enthalpy than Cl₂. Why?

(iv) Which noble gas is used in filling balloons for meteorological observations?

(v) Complete the following equation: XeF₂ + PF₅ →

An aromatic compound ‘A’ of molecular formula C₇H₆O₂ undergoes a series of reactions as shown below. Write the structures of A, B, C, D and E in the following reactions:

OR

(a) Write the structures of main products when benzene diazonium chloride reacts with the following reagents:

(i) H₃PO₂ + H₂O

(ii) CuCN/KCN

(iii) H₂O

(b) Arrange the following in the increasing order of their basic character in an aqueous solution: C₂H₅NH₂, (C₂H₅)₂NH, (C₂H₅)₃N

(c) Give a simple chemical test to distinguish between the following pair of compounds: C₆H₅-NH₂ and C₆H₅-NH-CH₃.