A large increase in the rate of a reaction for a rise in temperature is due to ____.
The decrease in the number of collisions
The increase in the number of activated molecules
The shortening of the mean free path
The lowering of the activation energy
Which of the following statements is not true according to collision theory of reaction rates?
Collision of molecules is a precondition for any reaction to occur
All collisions result in the formation of the products
Only activated collisions result in the formation of the products
Molecules which have acquired the energy of activation can collide effectively
The reaction rate at a given temperature becomes slower, then ____.
The free energy of activation is higher
The free energy of activation is lower
The entropy changes
The initial concentration of the reactants remains constant
A rise in temperature increases the velocity of a reaction. It is because it results in ____.
An increased number of molecular collisions
An increased momentum of colliding molecules
An increase in the activation energy
A decrease in the activation energy
If and are the activation energies of forward and reverse reactions and the reaction is known to be exothermic, then ____.
The energy of activation is ____.
The energy associated with the activated molecules
Threshold energy – energy of normal molecules
Threshold energy + energy of normal molecules
Energy of products – energy of reactants
The minimum energy a molecule should possess in order to enter into a fruitful collision is known as ____.
Reaction energy
Collision energy
Activation energy
Threshold energy
A zero order reaction is one whose rate is independent of ____.
Temperature of the reaction
The concentrations of the reactants
The concentration of the products
The material of the vessel in which the reaction is carried out
The rates of a certain reaction (dc/dt) at different times are as follows
Time Rate (mole litre–1 s –1 )
0
10
20
30
The reaction is ____.
Zero order
First order
Second order
Third order
/
400 s
600 s
800 s
1200 s