Atomos Test Generator Free PYQs ExamsMy practice Log in / Sign up free

Hydrocarbons

NEET 2016 (Phase 1)MCQEasyNot asked in last 5 yrs+4−1
Ques. 1NEET 2016 (Phase 1)

In the reaction H-C CH [(ii) CH3CH2Br](i) NaNH2/liq. NH3 X [(ii) CH3CH2Br](i) NaNH2/liq. NH3 Y, X and Y are

  1. X = 2-Butyne, Y = 2-Hexyne
  2. X = 1-Butyne, Y = 2-Hexyne
  3. X = 1-Butyne, Y = 3-Hexyne
  4. X = 2-Butyne, Y = 3-Hexyne

Answer

(3) X = 1-Butyne, Y = 3-Hexyne

Solution

Step 1: NaNH2 removes the acidic H of ethyne, HC CH NaNH2/liq. NH3 HC C-Na+, and the acetylide is then alkylated:

HC C-Na+ + CH3CH2Br HC C-CH2CH3 + NaBr

So X = CH3CH2C CH (1-Butyne).

Step 2: X still has a terminal H, so the same two steps repeat:

CH3CH2C CH NaNH2 CH3CH2C C-Na+

CH3CH2C C-Na+ + CH3CH2Br CH3CH2C CCH2CH3 + NaBr

So Y = CH3CH2C CCH2CH3 (3-Hexyne).

Answer: (3)

Keep practising — Hydrocarbons

Ques. 2NEET 2016 (Phase 2)

Which of the following can be used as halide component for Friedel-Crafts reaction?

  1. Chlorobenzene
  2. Bromobenzene
  3. Chloroethene
  4. Isopropyl chloride
Ques. 3NEET 2016 (Phase 2)

Which of the following compounds shall not produce propene by reaction with HBr followed by elimination or direct only elimination reaction ?

  1. [figure]
  2. H3C- H2 |C-CH2OH
  3. H2C=C=O
  4. H3C- H2 |C-CH2Br
Ques. 4NEET 2016 (Phase 2)

In the given reaction, [figure] the product P is

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
Ques. 5NEET 2016 (Phase 2)

The compound that will react most readily with gaseous bromine has the formula

  1. C3H6
  2. C2H2
  3. C4H10
  4. C2H4
Ques. 6AIPMT 2015

In the reaction with HCl, an alkene reacts in accordance with the Markovnikov's rule to give a product 1-chloro-1-methylcyclohexane. The possible alkene is

  1. [figure] (A)
  2. [figure] (B)
  3. (A) and (B)
  4. [figure]
Ques. 7AIPMT 2015

2,3-Dimethyl-2-butene can be prepared by heating which of the following compounds with a strong acid?

  1. (CH3)3CCH=CH2
  2. (CH3)2C=CHCH2CH3
  3. (CH3)2CHCH2CH=CH2
  4. (CH3)2CH- CH3 |CH-CH=CH2
Ques. 8AIPMT 2015

The oxidation of benzene by V2O5 in the presence of air produces

  1. maleic anhydride
  2. benzoic acid
  3. benzaldehyde
  4. benzoic anhydride.
Ques. 9AIPMT 2015 (Cancelled)

A single compound of the structure, [figure] is obtainable from ozonolysis of which of the following cyclic compounds?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
Ques. 10AIPMT 2015 (Cancelled)

The reaction of C6H5CH=CHCH3 with HBr produces

  1. C6H5CH2CH2CH2Br
  2. [figure]
  3. C6H5 Br |CHCH2CH3
  4. C6H5CH2 Br |CHCH3
Ques. 11AIPMT 2014

What products are formed when the following compound is treated with Br2 in the presence of FeBr3? [figure]

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]

All Hydrocarbons PYQs →

PDFDownload Hydrocarbons PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All NEET Chemistry chapters
Physical ChemistrySome Basic Concepts of ChemistryStructure of AtomStates of MatterThermodynamicsEquilibriumRedox ReactionsSolid StateSolutionsElectrochemistryChemical KineticsSurface Chemistry
Inorganic ChemistryClassification of Elements and Periodicity in PropertiesChemical Bonding and Molecular StructureHydrogens-Block Elementsp-Block Elements (Group 13 & 14)Environmental ChemistryGeneral Principles of Isolation of Elementsp-Block Elements (Group 15–18)d- and f-Block ElementsCoordination Compounds
Organic ChemistryOrganic Chemistry – Some Basic Principles and TechniquesIsomerismHydrocarbonsHaloalkanes and HaloarenesAlcohols, Phenols and EthersAldehydes, Ketones and Carboxylic AcidsAminesBiomoleculesPolymersChemistry in Everyday LifePrinciples Related to Practical Chemistry