Saturday, October 10, 2009

IIT-JEE-Chemistry-Final Revision Set No.58

Use the following key to choose the appropriate answer.
(a) If both assertion and reason are CORRECT, and reason is the CORRECT explanation of the assertion.
(b) If both assertion and reason are CORRECT, but reason is NOT the CORRECT explanation of the assertion.
(c) If assertion is CORRECT, but reason is INCORRECT.
(d) If assertion is INCORRECT, but reason is CORRECT.

1.
Dimethylsulphide is commonly used for the reduction of an ozonide of an alkene to get the carbonyl compounds.

It reduces the ozonide giving water soluble dimethyl sulphoxide and excess of it evaporates.


2.

Addition of bromine to trans-2-butene yields meso-2, 3-dibromobutane.

Bromine addition to an alkene is an electrophilic addition.

3.
Between SiCl4 and CCl4, only SiCl4 reacts with water.

SiCl4 is ionic and CCl4 is covalent.

4.
strongly acidic solutions, aniline becomes more reactive towards electrophilic reagents.

The amino group being completely protonated in strongly acidic solution, the lone pair of electrons of the nitrogen is no longer available for resonance.


5.
In any ionic solid (MX) with Schottky defects, the number of positive and negative ions are same.


Equal numbers of cation and anion vacancies are present.

Source JEE screening 2001

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