Arrange the following carbanions in order of their decreasing stability:

A. \(\mathrm{H}_3 \mathrm{C}-\mathrm{C} \equiv \mathrm{C}^{-}\)
B. \(\mathrm{H}-\mathrm{C} \equiv \mathrm{C}^{-}\)
C. \(\mathrm{H}_3 \mathrm{C}-\mathrm{{C}H_2^-}\)

 
1. A > B > C 2. B > A > C
3. C > B > A 4. C > A > B

Subtopic:  Electron Displacement Effects |
 72%
Level 2: 60%+
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The correct order of decreasing reactivity of the following compounds:

Chlorobenzene, 2,4-Dinitrochlorobenzene, and p-Nitrochlorobenzene

with an electrophile (E+)  is :

1. Chlorobenzene > p–Nitrochlorobenzene > 2,4-Dinitrochlorobenzene
2. p – Nitro chlorobenzene > 2, 4-Dinitrochlorobenzene > Chlorobenzene 
3. Chlorobenzene  > 2, 4-Dinitrochlorobenzene > p-Nitrochlorobenzene
4. 2, 4-Dinitrochlorobenzene > Chlorobenzene > p-Nitrochlorobenzene 

Subtopic:  Alkanes, Alkenes and Alkynes - Chemical Properties |
 71%
Level 2: 60%+
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Ethyne? Benzene 

The reagent used in the above conversion is:

1. Cr2O3

2. Alc. KOH

3. Red hot Fe

4. NaNH2/liq.NH3

Subtopic:  Aromatic Hydrocarbons - Reactions & Mechanism |
 90%
Level 1: 80%+
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Decreasing order of acidic behavior of benzene, n-hexane, and ethyne is:

1. Hexane > Ethyne > Benzene

2. Benzene > Hexane > Ethyne

3. Ethyne > Benzene > Hexane

4. Benzene > Ethyne > Hexene

Subtopic:  Alkanes, Alkenes and Alkynes - Chemical Properties |
 84%
Level 1: 80%+
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The products formed after ozonolysis of Pent-2-ene are:

1. Ethanal and Methanal 2. Ethanal and Propanal
3. Ethanal and Butanal 4. Ethanal and  Ethanol
Subtopic:  Alkanes, Alkenes and Alkynes - Chemical Properties |
 90%
Level 1: 80%+
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A compound possessing optical isomerism provided it has the molecular formula C7H16, would be:

1. 2,3-Dimethyl pentane 2. 2,2-Dimethyl butane
3. 2-Methyl hexane 4. None of the above
Subtopic:  Alkanes, Alkenes and Alkynes - Conformations and Hybridisation |
 75%
Level 2: 60%+
AIPMT - 2001
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 An alkene ‘A’ on ozonolysis gives a mixture of ethanal and pentan-3-one.
The IUPAC name of ‘A’ is :

1. 3-Ethylpent-2-ene

2. 3-Ethylpent-2- yne

3. 2-Ethylpent-3-ene

4. 3-Ethylpent-4-yne

Subtopic:  Alkanes, Alkenes and Alkynes - Chemical Properties |
 82%
Level 1: 80%+
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Benzene+CH3ClAlCl3C6H5CH3

The mechanism & intermediate involved in the above reaction are:

1. Aromatic electrophilic substitution & carbocation

2. Aromatic Nucleophilic substitution & carbanion

3. Aromatic free radical substitution & Free radical

4. Carbene based substitution reaction & Carbene

Subtopic:  Aromatic Hydrocarbons - Benzene - Structure, Preparation & Chemical Reactions |
 86%
Level 1: 80%+
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The product(s) obtained via oxymercuration (HgSO4 + H2SO4 ) of but-1-yne is -

1. CH3CH2-C||O-CH3

2. CH3CH2 CH2-CHO

3. CH3CH2CHO + HCHO

4. CH3 CH2COOH + HCOOH

Subtopic:  Alkanes, Alkenes and Alkynes - Chemical Properties |
 71%
Level 2: 60%+
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Which of the following hydrocarbon fuels has the highest octane rating?

1. Methane

2. Ethane

3. Iso-octane

4. Triptane

Subtopic:  Aliphatic Hydrocarbon- Physical Properties |
 74%
Level 2: 60%+
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