JEE MAIN PYQs CHEMISTRY QUESTIONS WITH DETAILED EXPLAINATIONS

DISCUSSION OF ALL QUESTIONS EXPLAINING CONCEPTS AND TRICKS
Q.The bond order and magnetic property of
acetylide ion are same as that of:(1) N2+ (2) O2+ (3) NO+ (4) O2-
Q. What is the number of unpaired electron(s) in the highest occupied molecular orbital of the following species : N2; N2+ ;O2; O2+ ?
(1) 2,1,0,1 (2) 0, 1, 0, 1
(3) 0,1,0,1 (4) 2,1,2,1
Q.According to MO theory the bond orders forO2 2−, CO and NO+ respectively, are:
(1) 1, 2 and 3 (2) 1,3 and 2
(3) 2,3 and 3 (4) 1, 3 and 3
Q. Given below are two statements: One is labelled
as Assertion (A) and the other is labelled as
Reason (R).
Assertion (A): The H-O-H bond angle in water
molecule is 104.5°
Reason (R): The lone pair - lone pair repulsion
of electrons is higher than the bond pair-bond
pair repulsion.
In the light of the above statements, choose the
correct answer from the options given below:
(1) (A) is false but (R) is true.
(2) (A) is true but (R) is false.
(3) Both (A) and (R) are true, and (R) is the
correct explanation of (A).
(4) Both (A) and (R) are true, but (R) is not the
correct explanation of (A).
Q.A central atom in a molecule has two lone pairs
of electrons and forms three single bonds. The
shape of this molecule is:
(1) trigonal pyramidal (2) T-shaped
(3) see-saw (4) planar triangular
Q. Arrange the following in increasing order of their covalent character.
(1) CaF2 (2) CaCl2 (3) CaBr2 (4) CaI2