71For the first one, I think the rates should be equal a
For second one I think it should be c
For 3, I think it should be a
Q1. When we nitrate benzene using conc. HNO3 + conc. H2SO4 let the rate of reaction be R1. If we nitrate benzene but instead of protium we have deuterium atoms, let the rate be R2.
(Assume that the substrate does NOT give much steric hindrance to the electrophile)
Then choose the correct statement.
a) R1=R2
b) R1>R2
c) R1<R2
d) Can't say
Q2 When benzene undergoes electrophilic substitution, then the activation energy for the second step i.e. removal of H is Ea1 say.
If instead of Protium atoms we have deuterium atoms, then the activation of the second step is say Ea2.
Then choose the correct relationship between Ea1 and Ea2.
a) Ea1 = Ea2
b) Ea1 > Ea2
c) Ea1 < Ea2
d) Can't say
Q3 When we sulphonate benzene using oleum let the rate of reaction be R1.
If we nitrate benzene but instead of protium we have deuterium atoms, let the rate be R2.
(Assume that the substrate does NOT give much steric hindrance to the electrophile)
Then choose the correct statement.
a) R1 = R2
b) R1 > R2
c) R1 < R2
d) Can't say
-
UP 0 DOWN 0 0 5
5 Answers
7171See this please more better clarity:
http://en.wikipedia.org/wiki/Kinetic_isotope_effect
1the answer for 1 should be R2>R1
its due to the higher vibrational energy of carbon deuterium bond