Which of the following halogen-exchange reactions is possible?
R(I + NaCI (
R(F + KCI (
CH3F + AgBr (
RCI + NaI (
Bond dipole moments increase in the order:
C(F< C( CI> C(Br C(F< C( CI< C(I C(I< C( Br< C(F C(I< C( Br< C(CI Addition of HBr gives same product in the presence or absence of peroxide when alkene is:
1-butene
isobutene
2,3-dimethyl-2-butene
propene
What is the final product of the following reaction?
CH3CH=CH2 + NBS (major)
CH3CH=CHCN
CH3CH=CHNC
CH2=CHCH2CN
CH2=CHCH2NC
Select incorrect statement:
Reactivity of alkyl halides towards EI or E2 reaction is 3o > 2o > 1o Alkyl Halides
EI reaction is stereospecific
Dehydrohalogenation is trans-elimination
EI and SN 1 reactions are competitive
The most suitable reagent for producing dichlorocarbene from chloroform is:
Sodium acetate
Potassium-t-butoxide
Trethyl amine
Pyridine
Which one of the following cannot undergo nucleophilic substitution under ordinary condition?
Allyl chloride
Benzyl chloride
n-Propyl chloride
Vinyl chloride
Which addition is syn type?
Both of the above
None of the above
C3H6CI2 (A) by hydrolysis forms C3H6O(B), B gives iodoform test if A is:
1,1-dichloropropane
1,2-dichloropropane
1,3-dichloropropane
2,2-dichloropropane
3-Phenylpropene on reaction with HBr gives (as a major product):
C6H5CH2CH(Br)CH3
CH3CH=CHCH3
CH3CH2CH=CH2
C5H5CH(Br)CH=CH2
Among the following the most reactive towards alcoholic KOH is :
CH2=CHBr
CH3COCH2CH2Br
CH3CH2Br
CH3CH2CI
When chloroform is exposed to air and sunlight the compound obtained is:
Chloral
Acetyl chloride
Phosgene
Methyl chloride
Alkynes are reduced to trans-alkene by Na/NH3. Reduction is due to:
Nascent hydrogen
Molecular hydrogen
Atomic hydrogen
Solvated electrons
Cis-trans isomerism is not possible in alkynes because of:
180o bond-engle at the carbon-carbon triple bond
Greater electrongativity of sp-hybridised carbon
Shorter bond length of carbon-carbon triple bond
Lesser stability of sp-hybridised state
In oxidative-hydroboration, intermediate is:
enol
carbene
Carboraction
carbanion
Consider following methods of converting alkyne into carbonyl compounds:
I: HgSO4/H2SO4
II: BH3. THF/H2O2.OH-
Terminal alkyne (other than HC(CH) changes to aldhyde by:
I
II
Both (a) and (b)
None of these
Only one type of carbonyl compound is obtained by hydration of the following alkynes:
CH ( CH or CH3C( CH
CH3C( CH or CH3CH2C ( CH
CH( CH or CH3C (CCH3
In all cases
What is the product when 1-butyne reacts with excess of HBr?
2,2-dibromobutane
2-bromobutane
1,1,2,2-tetrabromobutane
1,2-dibromobutene
I CH2=C=CH2
II CH3C( CH
III CH3C ( CH
Acetone is the major product in:
I, II
I, III
II, III
I, II, III
CH3C( CCH3 and CH3CH2C(CH can be distinguished by:
Ammoniacal AgNO3
Ammoniacal Cu2CI2
Both (a) and (b)
None of these
Which is the ethinylation reaction?
CH3C CCH3 + HCHO
CH3C CH + (CH3)2CO
CHH CH + CH3CH2CI
Consider following statements:
I: vinyl acetate is used in plastic industry.
II: vinyl cyanide and butadiene form buna-N synthetic rubber.
III: In the addition of HBr or Br2 to an alkyne, second addition is usually faster than the first
IV: Bromo alkene is more reactive than an alkyne
Select correct statements:
I, II
II, III
I, III
III, IV
When CH4, C2H2, C2H4 and C2H6 gases are passed through the Wolf-bottle containing ammoniacal AgNO3, then which one of the following gas does not come out from the bottle?
CH4
C2H2
C2H4
C2H6
Select correct statement(s):
Rate of hydrogenation of (CH=CH2> (CH=CH(
The (C(C( bond is reduced more readily than
C=C( bond
( (
Birch reaction is effective for reduction of terminal double (C=C) bond
All are correct statements
Reducing agent in Birch reduction is:
NaBH4 PtCI2
Na/Liquid NH3
RhCI(Ph3P)3
N2H4
Select correct statement(s):
The dipole moment of cis-2-butene is the vector sum of the CH3(C and C(H bond dipoles
Sp2-carbon is more electronegative than an sp3-carbon
NBS is used for brominating CHEMSITRY, Alkeness (ORGANIC CHEMISTRY) (ORGANIC CHEMISTRY) at the allylic position
All are correct statments
Which of the following has stereocentre?
1-pentene
2-pentene
Both of these
None of these
1-Butene is formed selectively from….on reaction with alcoholic KOH.
1-chlorobutane
2-chlorobutane
Both of these
None of these
Select correct statement(s):
The more stable the CHEMSITRY, Alkenes, the more easily it is formed
Et3N (triethylamine) can also be used for the dehydrohalogenation of alkyl halide
Less-substituted (OBJECTIVE CHEMSITRY) Alkenes in an elimination reaction is referred to as a Hofmann elimination product
All are correct statements
Alkane, C5H12, in which all H-atoms are equivalent is:
n-pentane
2-methylbutane
2,2-dimethylpropane
cyclopentane