The addition of a catalyst during a chemical reaction alters which of the following quantities?
A
Enthalpy
B
Activation energy
C
Entropy
D
Internal energy
Explanation
A catalyst provides an alternate path to the
reaction which has lower activation energy.
2
NEET 2016 Phase 2
MCQ (Single Correct Answer)
The decomposition of phosphine (PH3) on tungsten at low pressure is a first-order reaction. It is because the
A
rate is proportional to the surface coverage
B
rate is inversely proportional to the surface coverage
C
rate is independent of the surface coverage
D
rate of decomposition is very slow.
Explanation
At low pressure, rate is proportional to the
surface coverage and is of first order while at
high pressure it follows zero order kinetic due to
complete coverage of surface area.
3
NEET 2016 Phase 1
MCQ (Single Correct Answer)
The rate of first-order reaction is 0.04 mol L$$-$$1 s$$-$$1 at 10 seconds and 0.03 mol L$$-$$1 s$$-$$1 at 20 seconds after initiation of the reaction. The half-life period of the reaction is