PG TRB free online chemistry practice test

MARAN ACADEMY

PG TRB CHEMISTRY

  

 

1. The mechanism involving the Transition state is
   1.   SN1
   2.   SN2
   3.   E1
   4.   E2
2. SN1 reaction rates is increased for allylic substrate present at
   1.   1 and 2 position
   2.   1 and 3 position
   3.   1 and 4 position
   4.   3 and 5 position
3. Among the halides the best leaving group is
   
   1.   F-
   2.   Cl-
   3.   Br-
   4.   I -
4. .
   The reaction of benzene are mainly
   
   1.   Free radical substitution
   2.   Electrophilic substitution
   3.   Nucleophilic substitution
   4.   Nucleophilic addition
5. .
   The rate of enhancement by the neighbouring group is called
   
   1.   Anchimeric substitution
   2.   Achimeric assistance
   3.   Anchimeric addition
   4.   Anchimeric process
6. Walden inversion is related with
   1.   SN1
   2.   SN2
   3.   E1
   4.   E2
7. Select the electrophone
   1.   SO3
   2.   ROH
   3.   H2O
   4.   CN-
8. The strongest nucleophile is
   1.   H2O
   2.   OH-
   3.   RO-
   4.   CN-
9. Alkyl halides on treatment with Aq.KOH gives
   1.   Alkenes
   2.   alkynes
   3.   alcohols
   4.   alkonides
10. Tertiary alkyl halides undergo alkaline hydrolysis by this mechanism
    1.   SN1
    2.   SN2
    3.   E1
    4.   E2
11. Erythroes and threoes are
    1.   Enentiomers
    2.   Antipodes
    3.   Diastereoisomers
    4.   Conformations
12. In which projection nomenclature the molecule is written with the longest carbon chain placed vertically
    1.   wedge
    2.   newmann
    3.   fisher
    4.   sawhorse
13. Epimers are the two diasteromers which differ in the configuration of ------- chiral centre
    
    1.   1
    2.   2
    3.   3
    4.   4
14. The number of optically active forms of 2,3 dibromo succinic acid is
    1.   4
    2.   2
    3.   3
    4.   8
15. How many pairs of enentiomers possible for a compound with three distinct chiral centers?
    
    1.   3
    2.   4
    3.   2
    4.   8
16. Stereoisomers not related to each other as object and image are called
    1.   Enentiomers
    2.   Enentiomers
    3.   Diastereoisomers
    4.   Conformations
17. The absolute configuration of to asymmetric carbon atom of (+)Tartaric acid are
    1.   R,R
    2.   S,S
    3.   R,S
    4.   S,R
18. The plane of symmetry is also called
    1.   α-plane
    2.   β-plane
    3.   γ-plane
    4.   σ-plane
19. Process of separation of racemic mixture into optically isomer is known as
    1.   Resolution
    2.   Racemisation
    3.   walden inversion
    4.   epimerisation
20. Isomers which are nonsuper impossible mirror image of each other are called
    1.   Enentiomers
    2.   Antipodes
    3.   Diastereoisomers
    4.   Conformations