Q25 of 26 Page 1

A. Writhe the product(s) in each of the following reactions :

(i)


(ii)


(iii)


B. Write the mechanism of the following reaction :



OR


A. Write equations of the following reactions :


(i) Bromine in with phenol


(ii) Treat phenol with chloroform in the presence of aq.NaOH


(iii) Anisole reacts with HI


B. Distinguish between :


(i) Ethanol and Diethyl ether


(ii) Propanol and t-butyl alcohol


A.

(i) CH2=CH–CH2OH CH2=CH–CHO


PCC (Pyridinium chlorocobalt) is a mild oxidizing agent and therefore cannot oxidize further into –COOH from –CHO.


(ii)Phenol is reduced to benzene by Zn dust



(iii) Following reaction is as follows:



ortho substituted is a minor product because of steric hindrance.


B. Mechanism is as follows:



OR


A.


(i)



(ii)



(iii)



B.


(i)To distinguish between alcohol and ether the basic chemical test is to react with sodium ions. Alcohol gives positive and ether gives negative test


(ii) The most common test used to distinguish in between the primary, secondary, and tertiary alcohols are the Lucas test.


The Lucas reagent is a combined solution of HCl and ZnCl₂.


The primary alcohol (propanol) and the tertiary alcohol (tert-butyl alcohol) react with Lucas reagent and form products which are unstable and more stable respectively.


When the primary alcohol reacts, it gives a least stable reaction and so no turbidity is observed and the solution remains colourless.


When the tertiary alcohol reacts, it gives the most stable reaction and the solution turns turbid or cloudy quickly along with the formation of 2 differentiated layers at room temperature.


More from this chapter

All 26 →
22

A. For the complex write the hybridization, magnetic character and spin of the complex. (At. Number : Co=27)

B. Draw one of the geometrical isomers of the complex which is optically active.


 23

Due to the hectic and busy schedule, Mr Awasthi made his life full of tensions and anxiety. He started taking sleeping pills to overcome depression without consulting the doctor. Mr Roy, a close friend of Mr Awasthi advised him to stop taking sleeping pills and suggested to change his lifestyle by doing Yoga, meditation and some physical exercise. Mr Awasthi followed his friend’s advice and after a few days, he started feeling better.

After reading the above passage, answer the following :


A. What are the values (at least two) displayed by Mr Roy?


B. Why it is not advisable to take sleeping pills without consulting doctor?


C. What are tranquillizers? Give two examples.


 24

A. Account for the following :

(i) is more acidic than


(ii) is more covalent than


B. Draw the structures of :


(i) (ii)


OR


(i) Arrange the following in the increasing order of their reducing character :



(ii) Out of He and Xe, which one can easily form compound and why?


(iii) Write the conditions to maximize the yield of ammonia in Haber’s process.


(iv) Write two uses of Chlorine gas.


(v) How can you detect the presence of gas?


 26

A. Calculate the boiling point of the solution when 4g was dissolved in 100g of water. Assuming undergoes complete ionization.


B. Define the following terms :


(i) Colligative properties


(ii) Ideal solution


OR


A. When 2.56 g of sulphur was dissolved in 100 g of the freezing point lowered by 0.383 K. Calculate the formula of sulphur


B. Blood cells are isotonic with 0.9% sodium chloride solution. What happens if we place blood cells in a solution containing?


(i) 1.2% sodium chloride solution


(ii) 0.4% sodium chloride solution