Activation Energy and its Calculation NEET Questions

Physical Chemistry - Chemical Kinetics

Activation Energy and its Calculation MCQ Questions


7.
The unit of activation energy in SI system is:
A.
mol/L
B.
J/mol or kJ/mol
C.
J/s
D.
K/J
😑 View Answer Rough Work Error
ANSWER :
B. J/mol or kJ/mol
8.
When activation energy of a reaction is zero, the rate constant k:
A.
Becomes zero
B.
Equals R·T
C.
Equals the pre-exponential factor A
D.
Becomes infinity
😑 View Answer Rough Work Error
ANSWER :
C. Equals the pre-exponential factor A
9.
As temperature increases, the rate constant k according to Arrhenius equation:
A.
Decreases linearly
B.
Remains constant
C.
Increases exponentially
D.
First decreases then increases
😑 View Answer Rough Work Error
ANSWER :
C. Increases exponentially
10.
The fraction of molecules having energy equal to or greater than activation energy is given by:
A.
Ea/RT
B.
1 − e^(-Ea/RT)
C.
e^(-Ea/RT)
D.
e^(Ea/RT)
😑 View Answer Rough Work Error
ANSWER :
C. e^(-Ea/RT)
11.
The rate of reaction approximately doubles for every 10°C rise in temperature. This implies:
A.
The temperature coefficient is 10
B.
The reaction is first order
C.
The activation energy is zero
D.
The temperature coefficient is approximately 2
😑 View Answer Rough Work Error
ANSWER :
D. The temperature coefficient is approximately 2
12.
The activation energy of an exothermic reaction is:
A.
Equal to enthalpy change
B.
Greater than that of the reverse reaction
C.
Less than that of the reverse endothermic reaction
D.
Always zero
😑 View Answer Rough Work Error
ANSWER :
C. Less than that of the reverse endothermic reaction