Reactivity of Molecules Reaction Mechanism Flashcards
- Electronegativity is defined as the power of an atom in a
molecule to
a) Repel electrons towards itself
b) Attract electrons towards itself
c) Expand itself
d) All of the mentioned
b) Attract electrons towards itself
- How does the electronegativiy gets affected with the
negative oxidation state?
a) It decreases
b) It increases
c) It remains constant
d) None of the mentioned
a) It decreases
- The factors on which electronegativity depends upon
a) Valence state of atom
b) Hybridisation
c) Both valence state and hybridisation
d) None of the mentioned
c) Both valence state and hybridisation
- The electronegativity of sp2 hybridised atom will be
a) 3.29
b) 2.48
c) 3.69
d) 2.75
d) 2.75
- Arrange the following groups in the order of decreasing
(+I) effect.
a) C6H5O– > COO– > CR3 > CHR2 > H
b) C6H5O– > H > CR3 > CHR2 > COO–
c) CR3 > C6H5O– > H > COO– > CHR2
d) C6H5O– > COO– > CHR2 > CR3 > H
a) C6H5O– > COO– > CR3 > CHR2 > H
- Which of the following is a permanent electron
displacement effect?
a) Inductomeric
b) Electromeric
c) Inductive
d) All of the mentioned
c) Inductive
- Select the correct statement from the following option
a) When multiple bonds are present between two
different atoms, electromeric shift towards the more
electronegative atom takes place
b) When multiple bonds are present between two similar
atoms, the first possibility is symmetric alkenes or alkynes
c) When multiple bonds are present between two similar
atoms, the second possibility is asymmetric alkenes or
alkynes
d) All of the mentioned
d) All of the mentioned
- Arrange the following groups in the order of decreasing
(-I) effect.
a) CN > F > Br > Cl > COOH > I > H
b) COOH > CN > F > Br > Cl > I > H
c) H > COOH > CN > I > Cl > F > Cl
d) CN > COOH > F > Cl > Br > I > H
d) CN > COOH > F > Cl > Br > I > H
- Which of the following is an application of inductive
effect?
a) Bond length
b) Dipole moment
c) Strength of carboxylic acids
d) All of the mentioned
d) All of the mentioned
- Due to presence of C – X polar bond in alkyl halide,
alkyl halides are
a) More reactive than corresponding alkane
b) Less reactive than corresponding alkane
c) Equally reactive as corresponding alkane
d) None of the mentioned
a) More reactive than corresponding alkane
- Relative basic strength of amines does not depend upon
a) Inductive effect
b) Mesomeric effect
c) Steric effect
d) Stabilisation of cation by hydration
b) Mesomeric effect
- Which of the following is a temporary effect brought
into play at the requirement of attacking reagent?
a) Inductive effect
b) Mesomeric effect
c) Electromeric effect
d) Inductomeric effect
c) Electromeric effect
- Select the correct statement from the following option.
a) Conjugate effect is stronger than (-I) effect
b) Conjugate effect is weaker than (-I) effect
c) Conjugate effect is same as (-I) effect
d) None of the mentioned
a) Conjugate effect is stronger than (-I) effect
- When the complete transfer of π-electrons take place
away from the atom at the requirement of attacking
agent, it is called
a) (-E) effect
b) (+E) effect
c) (-I) effect
d) (+I) effect
b) (+E) effect
- Which of the following is an example of lewis base?
a) ZnCl2
b) BF3
c) NH3
d) FeCl2
c) NH3
- The positively charged and electron deficient
compounds which have a tendency to form a bond by
accepting the electron pair are known as
a) Electrophiles
b) Nucleophiles
c) Homophiles
a) Electrophiles
- Which of the following is an incorrect statement about
the nucleophiles?
a) They are electron rich
b) They possess an empty orbital to receive the electron
pair
c) They attack electron deficient centres
d) Examples are: OH–, NH3, H2O etc
b) They possess an empty orbital to receive the electron
pair
- Lewis acids are the examples of nucleophilic reagents.
a) True
b) False
b) False
- Which of the following is a resonance effect?
a) Inductive effect
b) Electromeric effect
c) Mesomeric effect
d) Inductomeric effect
c) Mesomeric effect
- Which of the following molecule will show highest
dipole moment?
a) CH3Cl
b) CH3Br
c) CH3F
d) CH3I
c) CH3F
- Those groups which are electron repelling and have
lesser electron attracting power than hydrogen show
a) (+E) effect
b) (-E) effect
c) (-I) effect
d) (+I) effect
d) (+I) effect
- In mesomeric effect, the electrons are transferred from
a) A multiple bonds to an atom
b) A multiple bonds to a single covalent bond
c) An atom with a lone pair to the adjacent single covalent
bond
d) All of the mentioned
d) All of the mentioned
- The phenomenon in which 2 or more structures,
involving identical position of atoms can be written for a
particular molecule, is called
a) Conjugation
b) Resonance
c) Hyper conjugation
d) Vibration
b) Resonance
- The resonance energy is defined as a difference in
energy between
a) Two consecutive resonating structures
b) Resonance hybrid and most unstable resonating
structure
c
d) First and last resonating structures
a) Resonating structures have a real existence
- Select the incorrect option from the following option.
a) Resonating structures have a real existence
b) The actual structure lies between various possible
resonating structures
c) Resonating structures are useful as they allow us to
describe molecules
d) None of the mentioned
a) Resonating structures have a real existence
- Which of the following is an application of mesomeric
effect?
a) Dipole moment
b) Strength of acids and bases
c) Bond length
d) All of the mentioned
d) All of the mentioned
- Dipole moment of CH3-CH2-Cl > CH2=CH-Cl.
a) True
b) False
a) True
- Select the correct statement from the following option.
a) Benzene ring has two different types of bond length for
single and double bonds
b) All the bond length in benzene ring is equal due to
hyperconjugation
c) All the bond length in benzene ring is equal due to
resonance
d) All of the mentioned
c) All the bond length in benzene ring is equal due to
resonance
- Greater the number of resonating structures for a given
intermediate,
a) Less will be its stability
b) More will be its stability
c) It will not affect its stability
d) None of the mentioned
b) More will be its stability
- Which of the following is known as Baker-Nathan
effect?
a) Mesomeric effect
b) Inductive effect
c) Hyperconjugation
d) Electromeric effect
c) Hyperconjugation
- Phenyl group show
a) (+M) effect
b) (+E) effect
c) (+I) effect
d) (-M) effect
d) (-M) effect
- The resonance energy (kCal/mol) of tertiary butyl is
a) 9
b) 10
c) 11
d) 12
d) 12
- Hyperconjugation involves the delocalisation of
a) ς bond orbital
b) π bond orbital
c) Both ς and π bond orbital
d) None of the mentioned
a) ς bond orbital
- Number of hyperconjugation structures in isopropyl
radical is
a) 3
b) 6
c) 9
d) 12
b) 6
- Larger the number of hyperconjugation structures, the
stability of free radicals will
a) Increase
b) Decrease
c) Remains same
d) None of the mentioned
a) Increase
- The breaking of a covalent bond in such a way that each
atom separates with one electron of the shared pair is
called
a) Homolytic fission
b) Heterolytic fission
c) Monolytic fission
d) Morpholytic fission
a) Homolytic fission
- Ethene is devoid of any alpha hydrogen so
hyperconjugation is not possible.
a) True
b) False
a) True
- Which of the following is a consequence of Baker
Nathan effect?
a) It is helpful in explaining the directive influence of alkyl
groups in aromatic alkyl benzene
b) It is helpful in explaining the relative stability of alkenes
c) It is helpful in explaining the relative stabilities of alkyl
carbocations
d) All of the mentioned
d) All of the mentioned
- On increasing the number of α-hydrogens, the number
of hyperconjugation structures will
a) Decrease
b) Increase
c) Remains same
d) None of the mentioned
b) Increase
- When the contributing structure contains the same
number of two-electron bonds as the normal lewis
formula, it will be
a) Heterovalent hyperconjugation
b) Sacrificial hyperconjugation
c) Isovalent hyperconjugation
d) All of the mentioned
c) Isovalent hyperconjugation
- The compound that can be most readily sulphonated is
a) Benzene
b) Toluene
c) Nitrobenzene
d) Chlorobenzene
b) Toluene