Solved papers for NEET Chemistry NEET PYQ-IUPAC and Isomerism

done NEET PYQ-IUPAC and Isomerism Total Questions - 42

• question_answer1) IUPAC name of the compounds   [AIPMT 1998]
  A)
  trans-3 iodo- 4 chloro-3-pentene
  done clear
  B)
  cis-2-chloro-3-iodo-2-pentene
  done clear
  C)
  trans-2-chloro-3-iodo-2-pentene
  done clear
  D)
  cis-3-iodo-4-chloro-3-pentene
  done clear
  View Answer play_arrow

• question_answer2) Which of the following compounds is not chiral?                                        [AIPMT 1998]
  A)
  \[DC{{H}_{2}}C{{H}_{2}}C{{H}_{2}}Cl\]
  done clear
  B)
  \[C{{H}_{3}}C{{H}_{2}}CHDCl\]
  done clear
  C)
  \[C{{H}_{3}}CHDC{{H}_{2}}Cl\]
  done clear
  D)
  \[C{{H}_{3}}CHClC{{H}_{2}}D\]
  done clear
  View Answer play_arrow

• question_answer3) But-2-ene exhibits cu-trans isomerism due to: [AIPMT 2000]
  A)
  rotation around \[{{C}_{2}}{{C}_{3}}\] double bond
  done clear
  B)
  rotation around \[{{C}_{3}}{{C}_{4}}\] sigma bond
  done clear
  C)
  rotation around \[{{C}_{1}}{{C}_{2}}\] bond
  done clear
  D)
  restricted rotation around \[>C=C<\] bond
  done clear
  View Answer play_arrow

• question_answer4) Among the following alkenes,        [AIPMT 2000] 1-butene       cis-2-butene      trans-2-2butene        I                      II                          III the decreasing order of stability is:
  A)
                                                                               II > I > III
  done clear
  B)
  III > II > I
  done clear
  C)
  III > I > II
  done clear
  D)
  I > II > III
  done clear
  View Answer play_arrow

• question_answer5) The dihedral angle between two \[C-H\] bonds in the staggered conformation of ethane is:        [AIPMT 2000]
  A)
  \[{{60}^{o}}\]
  done clear
  B)
  \[{{180}^{o}}\]
  done clear
  C)
  \[{{0}^{o}}\]
  done clear
  D)
  \[{{120}^{o}}\]
  done clear
  View Answer play_arrow

• question_answer6) The (R) - and (S) - enantiomers of an optically active compound differ in:          [AIPMT 2000]
  A)
  their solubility in a chiral solvents
  done clear
  B)
  their reactivity with a chiral reagents
  done clear
  C)
  their optical rotation of plane polarised light
  done clear
  D)
  their melting points
  done clear
  View Answer play_arrow

• question_answer7) The incorrect IUPAC name is:       [AIPMT 2001]
  A)
  \[\underset{\text{2, methyl-3-butanone}}{\mathop{C{{H}_{3}}-\underset{\begin{smallmatrix}  || \\  O \end{smallmatrix}}{\mathop{C}}\,-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{3}}}}\,\]
  done clear
  B)
  \[\underset{\text{2, 3-dimethyl pentane}}{\mathop{C{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-\underset{\begin{smallmatrix}  | \\  C{{H}_{2}}-C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{3}}}}\,\]
  done clear
  C)
  \[\underset{\text{4-methyl-2-pentyne}}{\mathop{C{{H}_{3}}-C\equiv CCH{{(C{{H}_{3}})}_{2}}}}\,\]
  done clear
  D)
  \[\underset{\text{2-bromo-3-chlorobutane}}{\mathop{C{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  Cl \end{smallmatrix}}{\mathop{CH}}\,-\underset{\begin{smallmatrix}  | \\  Br \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{3}}}}\,\]
  done clear
  View Answer play_arrow

• question_answer8) A compound of molecular formula \[{{C}_{7}}{{H}_{16}}\] shows optical isomerism, compound will be:       [AIPMT 2001]
  A)
  2, 3-dimethyI pentane
  done clear
  B)
  2, 2-dimethyl butane
  done clear
  C)
  2-methyl hexane
  done clear
  D)
  none of the above
  done clear
  View Answer play_arrow

• question_answer9) IUPAC name of die following is:  [AIPMT 2002]             \[C{{H}_{2}}=\text{ }CHC{{H}_{2}}C{{H}_{2}}C\equiv CH\]
  A)
  1, 5-hexenyne
  done clear
  B)
  1 - hexene-5-yne
  done clear
  C)
  1-hexyne-5-ene
  done clear
  D)
  1, 5-hexynene
  done clear
  View Answer play_arrow

• question_answer10) \[\overset{\begin{smallmatrix}  \odot - \\  \centerdot \,\,\centerdot  \end{smallmatrix}}{\mathop{C{{H}_{2}}}}\,-\underset{\begin{smallmatrix}  |\,\,\,| \\  O \end{smallmatrix}}{\mathop{C}}\,-C{{H}_{3}}\] and \[C{{H}_{2}}=\underset{\begin{align}   & | \\  & _{\centerdot }^{\centerdot }O\,_{\centerdot }^{\centerdot } \\  & \centerdot \,\,\centerdot  \\  & \odot - \\ \end{align}}{\mathop{C}}\,-C{{H}_{3}}\] are:  [AIPMT 2002]
  A)
  resonating structures
  done clear
  B)
  tautomers
  done clear
  C)
  geometrical isomers
  done clear
  D)
  optical isomers
  done clear
  View Answer play_arrow

• question_answer11) Geometrical isomers are differ in              [AIPMT 2002]
  A)
  position of functional group
  done clear
  B)
  position of atoms
  done clear
  C)
  spatial arrangement of atoms
  done clear
  D)
  length of carbon chain
  done clear
  View Answer play_arrow

• question_answer12) Name of the compound given below is:                                                     [AIPMT 2003]
  A)
  2, 3-diethylheptane
  done clear
  B)
  5-ethyl-6-methyloctane
  done clear
  C)
  4-ethyl-3-methyloctane
  done clear
  D)
  3-methyl-4-ethyloctane
  done clear
  View Answer play_arrow

• question_answer13) Which of the following pairs of compounds are enantiomers?                                   [AIPMT 2003]
  A)
  
  done clear
  B)
  
  done clear
  C)
  
  done clear
  D)
  
  done clear
  View Answer play_arrow

• question_answer14) The molecular formula of diphenyl methane How many structural isomers are possible when one of the hydrogen is replaced by a chlorine atom?                   [AIPMT (S) 2004]
  A)
  6
  done clear
  B)
  4
  done clear
  C)
  8
  done clear
  D)
  7
  done clear
  View Answer play_arrow

• question_answer15) Which one of the following pairs represents stereoisomerism?     [AIPMT (S) 2005]
  A)
  Chain isomerism and rotational isomerism
  done clear
  B)
  Structural isomerism and geometric isomerism
  done clear
  C)
  Linkage isomerism and geometric isomerism
  done clear
  D)
  Optical isomerism and geomertric isomerism
  done clear
  View Answer play_arrow

• question_answer16) The chirality of the compound [AIPMT (S) 2005]
  A)
  R
  done clear
  B)
  S
  done clear
  C)
  Z
  done clear
  D)
  E
  done clear
  View Answer play_arrow

• question_answer17) Names of some compounds are given. Which one is not correct in IUPAC system?      [AIPMT (S) 2005]
  A)
  \[\underset{3-methyl-2\text{ }bu\tan ol}{\mathop{C{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  OH \end{smallmatrix}}{\mathop{CH}}\,-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{3}}}}\,\]
  done clear
  B)
  \[\underset{4-methyl-2-pentyne}{\mathop{C{{H}_{3}}-C\equiv C}}\,-CH{{(C{{H}_{3}})}_{2}}\]
  done clear
  C)
  \[\underset{2-ethyl-3\text{ }methyl-but-1-ene}{\mathop{C{{H}_{3}}-C{{H}_{2}}-\underset{\begin{smallmatrix}  || \\  C{{H}_{2}} \end{smallmatrix}}{\mathop{C}}\,-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{3}}}}\,\]
  done clear
  D)
  \[\underset{3-methyl-4\text{ }ehtyl\text{ }hep\tan e}{\mathop{C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}-\underset{\begin{smallmatrix}  | \\  C{{H}_{2}}C{{H}_{3}} \end{smallmatrix}}{\mathop{CH}}\,-\overset{\begin{smallmatrix}  C{{H}_{3}} \\  | \end{smallmatrix}}{\mathop{CH}}\,-C{{H}_{2}}C{{H}_{3}}}}\,\]
  done clear
  View Answer play_arrow

• question_answer18) The best method for the separation of naphthalene and benzoic acid from their mixture is:        [AIPMT (S) 2005]
  A)
  chromatography
  done clear
  B)
  crystallisation
  done clear
  C)
  distillation
  done clear
  D)
  sublimation
  done clear
  View Answer play_arrow

• question_answer19) The general molecular formula, which represents the homologous series of alkanols is:  [AIPMT (S) 2006]
  A)
  \[{{C}_{n}}{{H}_{2n}}{{O}_{2}}\]
  done clear
  B)
  \[{{C}_{n}}{{H}_{2n}}O\]
  done clear
  C)
  \[{{C}_{n}}{{H}_{2n+1}}O\]
  done clear
  D)
  \[{{C}_{n}}{{H}_{2n+2}}O\]
  done clear
  View Answer play_arrow

• question_answer20) Which of the following is not chiral?                                                  [AIPMT (S) 2006]
  A)
  2-butanol
  done clear
  B)
  2, 3-dibromopentane
  done clear
  C)
  3-bromopentane
  done clear
  D)
  2-hydroxypropanoic acid
  done clear
  View Answer play_arrow

• question_answer21) The IUPAC name of  is:  [AIPMT (S) 2006]
  A)
  3, 4-dimethylpentanoyl chloride
  done clear
  B)
  1-chloro-1-oxo-2, 3-dimethylpentane
  done clear
  C)
  2-ethyl-3-methyIbutanoyi chloride
  done clear
  D)
  2, 3-dimethylpentanoyl chloride
  done clear
  View Answer play_arrow

• question_answer22) If there is no rotation of plane polarized light by a compound in a specific solvent, thought to be chiral, it may mean that:       [AIPMT (S) 2007]
  A)
  the compound is certainly a chiral
  done clear
  B)
  the compound is certainly meso
  done clear
  C)
   there is no compound in die solvent
  done clear
  D)
  the compound may be a racemic mixture
  done clear
  View Answer play_arrow

• question_answer23) \[C{{H}_{3}}-CHCl-C{{H}_{2}}-C{{H}_{3}}\] has a chiral centre. Which one of the following represents its R configuration? [AIPMT (S) 2007]
  A)
  \[\begin{align}   & \,\,\,\,\,\,\,\,\,\,\,\,\,\,{{C}_{2}}{{H}_{5}} \\  & {{H}_{3}}C-\overset{|}{\mathop{\underset{|}{\mathop{C}}\,}}\,-Cl \\  & \,\,\,\,\,\,\,\,\,\,\,\,\,\,H \\ \end{align}\]
  done clear
  B)
  \[\begin{align}   & \,\,\,\,\,\,\,\,\,\,\,\,\,\,{{C}_{2}}{{H}_{5}} \\  & H-\overset{|}{\mathop{\underset{|}{\mathop{C}}\,}}\,-C{{H}_{3}} \\  & \,\,\,\,\,\,\,\,\,\,\,\,\,\,Cl \\ \end{align}\]
  done clear
  C)
  \[\begin{align}   & \,\,\,\,\,\,\,\,\,{{C}_{2}}{{H}_{5}} \\  & Cl-\overset{|}{\mathop{\underset{|}{\mathop{C}}\,}}\,-C{{H}_{3}} \\  & \,\,\,\,\,\,\,\,\,\,H \\ \end{align}\]
  done clear
  D)
  \[\begin{align}   & \,\,\,\,\,\,\,\,\,C{{H}_{3}} \\  & H-\overset{|}{\mathop{\underset{|}{\mathop{C}}\,}}\,-Cl \\  & \,\,\,\,\,\,\,\,\,{{C}_{2}}{{H}_{5}} \\ \end{align}\]
  done clear
  View Answer play_arrow

• question_answer24) The IUPAC name of the compound having the formula \[CH\equiv C-CH=C{{H}_{2}}\] is [AIPMT (S) 2009]
  A)
  3-butene-1-yne
  done clear
  B)
  1-butyn-3-ene
  done clear
  C)
  but-1-yne-3-ene
  done clear
  D)
  1-butene-3-yne
  done clear
  View Answer play_arrow

• question_answer25) Which of the following compounds will exhibit cis-trans (geometrical) isomerism?         [AIPMT (S) 2009]
  A)
  2-butene
  done clear
  B)
  Butanol
  done clear
  C)
  2-butyne
  done clear
  D)
  2-butenol
  done clear
  View Answer play_arrow

• question_answer26) Which/of the following conformers for ethylene glycol is most stable?           [AIPMT (M) 2010]
  A)
  
  done clear
  B)
   
  done clear
  C)
  
  done clear
  D)
  
  done clear
  View Answer play_arrow

• question_answer27) The IUPAC name of the compound\[C{{H}_{3}}CH=CHC\equiv CH\]           [AIPMT (M) 2010]
  A)
  pent-4-yn-2-ene
  done clear
  B)
  pent-3-en-1-yne
  done clear
  C)
  pent-2-en-4-yne
  done clear
  D)
  pent-1-yn-3-ene
  done clear
  View Answer play_arrow

• question_answer28) The correct IUPAC name of the compound is                            [AIPMT (S) 2011]
  A)
  3-ethyl-4-ethenylheptane
  done clear
  B)
  3-ethyl-4-propylhex-5-ene
  done clear
  C)
  3-(1-ethyl propyl) hex-1-ene
  done clear
  D)
  4-ethyl-3-propylhex-1-ene
  done clear
  View Answer play_arrow

• question_answer29) The IUPAC name of the following compound                     [AIPMT (M) 2011]
  A)
  is trans-2-chloro-3-iodo-2-pentene
  done clear
  B)
  cis-3-iodo-4-chloro-3-pentene
  done clear
  C)
  rrans-3-iodo-4-chloro-3-pentene
  done clear
  D)
  cis-2-chloro-3-iodo-2-pentene
  done clear
  View Answer play_arrow

• question_answer30) Which nomenclature is not according to IUPAC system?                                    [AIPMT (S) 2012]
  A)
  \[\underset{1-bromo\,pro-2-ene}{\mathop{Br-C{{H}_{2}}-CH=C{{H}_{2}}}}\,\]
  done clear
  B)
  \[\underset{4-bromo-2,\,4-\dimethylhexane}{\mathop{C{{H}_{3}}-C{{H}_{2}}-\underset{\begin{smallmatrix}  | \\  Br \end{smallmatrix}}{\overset{\begin{smallmatrix}  C{{H}_{3}} \\  | \end{smallmatrix}}{\mathop{C}}}\,-C{{H}_{2}}-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\mathop{C}}\,HC{{H}_{3}}}}\,\]
  done clear
  C)
  
  done clear
  D)
  \[\underset{5-oxohexanoic\,acid}{\mathop{C{{H}_{3}}-\underset{\begin{smallmatrix}  || \\  O \end{smallmatrix}}{\mathop{C}}\,-C{{H}_{2}}-C{{H}_{2}}}}\,-C{{H}_{2}}COOH\]
  done clear
  View Answer play_arrow

• question_answer31) Which of the following acids does not exhibit optical isomerism?             [AIPMT (S) 2012]
  A)
  Maleic acid
  done clear
  B)
  \[\alpha -\]amino acids
  done clear
  C)
  Lactic acid
  done clear
  D)
  Tartaric acid
  done clear
  View Answer play_arrow

• question_answer32) Structure of the compound whose IUPAC name is 3-ethyl-2-hydroxy- 4-methylhex-3-en-5-ynoic acid is                                                                                                                                      [NEET 2013]
  A)
  
  done clear
  B)
   
  done clear
  C)
  
  done clear
  D)
  
  done clear
  View Answer play_arrow

• question_answer33) The structure of isobutyl group in an organic compound is                             [NEET 2013]
  A)
  
  done clear
  B)
  \[C{{H}_{3}}-\underset{{}}{\mathop{CH}}\,-C{{H}_{2}}-C{{H}_{3}}\]
  done clear
  C)
  \[C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}-C{{H}_{2}}-\]
  done clear
  D)
  \[C{{H}_{3}}-\underset{\begin{smallmatrix}  | \\  C{{H}_{3}} \end{smallmatrix}}{\overset{\begin{smallmatrix}  C{{H}_{3}} \\  | \end{smallmatrix}}{\mathop{C}}}\,-\]
  done clear
  View Answer play_arrow

• question_answer34) The order of stability of the following tatutomeric compound is                                    [NEET 2013]
  A)
  I > II > III
  done clear
  B)
  III > II > I
  done clear
  C)
  II > l> III
  done clear
  D)
  II > III > I
  done clear
  View Answer play_arrow

• question_answer35) The enolic form of ethyl acetoacetate as below has                                 [NEET 2015 ]
  A)
  18 sigma bonds and 2 pi-bonds
  done clear
  B)
  16 sigma bonds and 1 pi-bond
  done clear
  C)
  9 sigma bonds and 2 pi-bonds
  done clear
  D)
  9 sigma bonds and 1 pi-bond
  done clear
  View Answer play_arrow

• question_answer36) Given,                                  [NEET 2015 ]    Which of the given compounds can exhibit tautomerism?
  A)
  I and II
  done clear
  B)
  I and III
  done clear
  C)
  II and III
  done clear
  D)
  I, II and III
  done clear
  View Answer play_arrow

• question_answer37) The number of structural isomers possible from the molecular formula  is            [NEET 2015 (Re)]
  A)
  4
  done clear
  B)
  5
  done clear
  C)
  2
  done clear
  D)
  3
  done clear
  View Answer play_arrow

• question_answer38) Two possible stereo-structures of  which are optically active, are called       [NEET 2015 (Re)]
  A)
  diastereomers
  done clear
  B)
  atropisomers
  done clear
  C)
  enantiomers
  done clear
  D)
  mesomers
  done clear
  View Answer play_arrow

• question_answer39) The correct statement regarding the comparison of staggered and eclipsed conformation of ethane, is :-                     [NEET - 2016]
  A)
  The staggered conformation of ethane is less stable than eclipsed conformation, because staggered conformation has torsional strain
  done clear
  B)
  The eclipsed conformation of ethane is more stable than staggered conformation, because eclipsed conformation has no torsional strain
  done clear
  C)
  The eclipsed conformation of ethane is more stable than staggered conformation even through the eclipsed conformation has torsional strain
  done clear
  D)
  The staggered conformation of ethane is more stable than eclipsed conformation, because staggered conformation has no torsional strain.
  done clear
  View Answer play_arrow

• question_answer40) Which of the following biphenyls is optically active?
  A)
  
  done clear
  B)
  
  done clear
  C)
  
  done clear
  D)
  
  done clear
  View Answer play_arrow

• question_answer41) The IUPAC name of the compound [NEET-2017]
  A)
  3-keto-2-methylhex-5-enal
  done clear
  B)
  3-keto-2-methylhex-4-enal
  done clear
  C)
  5-formylhex-2-en-3-one
  done clear
  D)
  5-methyl-4-oxohex-2-en-5-al
  done clear
  View Answer play_arrow

• question_answer42) With respect to the conformers of ethane, which of the following statements is true?  [NEET-2017]
  A)
  Both bond angles and bond length remains same
  done clear
  B)
  Bond angle remains same but bond length changes
  done clear
  C)
  Bond angle changes but bond length remains
  done clear
  D)
  Both bond angle and bond length change
  done clear
  View Answer play_arrow