Which of the following compounds have highest melting point?
Only I
Only II
I and II
II and III
B.
Only II
Compound (II) is most symmetrical because it has both CH3 groups and Cl atoms p-to each other. Therefore, it fits in the crystal lattice better than the other two isomers and hence it has highest melting point.
Addition ofwater to alkynes occurs in acidic medium and in the presence of Hg2+ ions as a catalyst. Which of the following products will be formed on addition of water to but-1-yne under these conditions?
CH3CH2CH2CHO
CH3CH2COCH3
CH3CH2COOH
CH3COOH + HCHO
Which one of these is not true for benzene?
It forms only one type of mono-substituted product
There are three carbon-carbon single bonds and three carbon-carbon double bonds
Heat of hydrogenation of benzene is less than its theoretical value
The bond angle between carbon-carbon bonds is 120°
Which of the following statement is correct ?
+I group stabilises a carbocation
+I group stabilises a carbanion
-I group stabilises a carbocation
-I group stabilises a free radical
Which of the following can give a Grignard reagent when reacted with magnesium in dry ether?
C2H6
C2H5Cl
C2H5OH
C2H5CN
t-butyl chloride preferably undergo hydrolysis by
SN1 mechanism
SN2 mechanism
Any of (a) and (b)
None of these
Iodoform gives a precipitate with AgNO3 on heating but chloroform does not because
C - I bond in iodoform is weak and C - Cl bond in chloroform is strong
chloroform is covalent
iodoform is ionic
None of the above