The correct order of increasing bond angles in the following species is
A
Cl2O < ClO2 < ClO$$_2^ - $$
B
ClO2 < Cl2O < ClO$$_2^ - $$
C
Cl2O < ClO$$_2^ - $$ < ClO2
D
ClO$$_2^ - $$ < Cl2O < ClO2
Explanation
The correct order of increasing bond angles is
ClO$$_2^ - $$ < Cl2O < ClO2
3
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
The tendency of BF3, BCl3 and BBr3 to behave as Lewis acid decreases in the sequence
A
BCl3 > BF3 > BBr3
B
BBr3 > BCl3 > BF3
C
BBr3 > BF3 > BCl3
D
BF3 > BCl3 > BBr3
Explanation
In BF3, p-p overlap between B and F is
maximum due to identical size and energy of
p-orbitals, so electron deficiency in boron of BF3
is neutralized partially to the maximum extent by
back donation. Also, the tendency to back
donate decreases from F to I. So the order will
be:
BBr3 > BCl3 > BF3
4
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
Which one of the following molecular hydrides acts as a Lewis acid?
A
NH3
B
H2O
C
B2H6
D
CH4
Explanation
Among the given molecules, only diborane(B2H6) is
electron deficient i.e., it does not complete octet.
Thus, it acts as a Lewis acid.
NH3 and H2O being electron rich species behave as
Lewis base.
Questions Asked from p-Block Elements
On those following papers in MCQ (Single Correct Answer)
Number in Brackets after Paper Indicates No. of Questions