CBSE
Assertion : Thiophene present in commercial benzene as an impurity can be removed by shaking the mixture with cold concentrated H2SO4.
Reason : Thiophene is a heterocyclic aromatic compound.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
What is the correct order of basicity among the following compounds ?
II > I > III > IV
I > II > III > IV
III > I > II > IV
I > III > II > IV
Which one of the following is the most stable reactive intermediate?
Which of the following is an electrophile?
CCl2
CH
H2O
NH3
Ease of nucleophilic addition in the given compounds is
I > III > II
II > III > I
II > I > III
III > I > II
Select the correct statement.
Geometrical isomer may differ in dipole moment and visible/UV spectra.
Complexes of the type [Ma3b3] can also have facial (fac) and meridional (mer) isomer.
No optical isomer exists for the complex trans- [Co(en)2Cl2]+.
All of these.
Which of the following species is not aromatic?
Benzene
Cyclooctatetraenyl dianion
Tropylium ion
Cyclopentadienyl cation
Which of the following compounds is aromatic in nature?
Which ofthe following complexes exists as pair of enantiomers ?
trans-[Co(en)2Cl2]+
[Co(NH3)2Cl2]+
[Co{P(C2H5)3}2ClBr]
[Cr(en)3]3+
Arrange the following nucleophiles in the decreasing order of nucleophilicity :
(A) CH3COO-
(B) CH3O-
(C) CN-
(D)
C, B, A, D
A, B, C, D
C, C, B, A
B, C, A, D