Subject

Chemistry

Class

CBSE Class 12

Pre Boards

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Sample Papers

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 Multiple Choice QuestionsShort Answer Type

41.

Write the structures of the main products in the following reaction:


42.

Write the structures of the main products in the following reaction:


43.

(A), (B) and (C) are three non-cyclic functional isomers of a carbonyl compound with molecular formula C4H8O .
Isomers (A) and (C) give positive Tollen’s test whereas isomer (B) does not give Tollen’s test but gives positive Iodoform test. Isomers (A) and (B) on reduction with Zn(Hg)/conc. HCl give the same product (D).

(a) Write the structures of (A), (B), (C) and (D)
(b) Out of (A), (B) and (C) isomers, which one is least reactive towards addition of HCN ?


44.

Write the structure of the product when chlorobenzene is treated with methyl chloride in the presence of sodium metal and dry ether.


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45.

Write the structure of the alkene formed by dehydrohalogenation of 1-bromo-1-methylcyclohexane with alcoholic KOH.


46.

Define the following with an example:

Polysaccharides


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47.

Define the following with an example:

Denatured protein


When a protein in its native form, is subjected to physical change like a change in temperature or chemical change like a change in pH, the hydrogen bonds are disturbed. Due to this, globules unfold and helix gets uncoiled and protein loses its biological activity. This is called denaturation of the protein.


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48.

Define the following with an example:

Essential amino acids


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49.

Write the product when D-glucose reacts with conc. HNO3


50.

Amino acids show amphoteric behaviour. Why?


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