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.
2
AIPMT 2009
MCQ (Single Correct Answer)
Among the following which is the strongest oxidising agent?
A
Br2
B
I2
C
Cl2
D
F2
Explanation
Standard reduction potential of halogens are positive and decrease from fluorine to iodine. So, F2 is the strongest oxidizing agent.
3
AIPMT 2009
MCQ (Single Correct Answer)
The straight chain polymer is formed by
A
hydrolysis of CH3SiCl3 followed by condensation polymerisation
B
hydrolysis of (CH3)4Si by addition polymerisation
C
hydrolysis of (CH3)2SiCl2 followed by condensation polymerisation
D
hydrolysis of (CH3)3SiCl followed by condensation polymerisation.
Explanation
Hydrolysis of (CH3)2SiCl2 followed by
condensation polymerization.
4
AIPMT 2009
MCQ (Single Correct Answer)
The stability of +1 oxidation state among Al, Ga, In and Tl increases in the sequence
A
Al < Ga < In < Tl
B
Tl < In < Ga < Al
C
In < Tl < Ga < Al
D
Ga < In < Al < Tl
Explanation
The given elements belong to 13th group.
The elements mainly exhibit +3 and +1 oxidation
states. As we know, the stability of lower oxidation
state i.e., +1 state, increases on moving down the
group due to inert pair effect. The, stability follows
the order :
Al < Ga < In < Tl
Questions Asked from p-Block Elements
On those following papers in MCQ (Single Correct Answer)
Number in Brackets after Paper Indicates No. of Questions
