The decomposition of phosphine (PH₃) on tungsten at low pressure is a first-order reaction. It is because the

(1) rate is proportional to the surface coverage

(2) rate is inversely proportional to the surface coverage

(3) rate is independent of the surface coverage

(4) rate of decomposition is very slow

The rate of a first-order reaction is 0.04 mol L^-1 s^-1 at 10 sec and 0.03 mol L^-1 s^-1 at 20 sec after initiation of the reaction. The half-life period of the reaction is

1. 34.1 s

2. 44.1 s

3. 54.1 s

4. 24.7 s

The activation energy of a reaction can be determined from the slope of the graph between : 

1. ln K vs T

2. ln $\frac{\mathrm{K}}{\mathrm{T}}$ vs T

3. ln K vs $\frac{1}{\mathrm{T}}$

4. $\frac{\mathrm{T}}{\ln \mathrm{K}} vs \frac{1}{T}$

If the half-life is independent of its initial concentration, then the order of the reaction is:

1. 0 

2. 1

3. 3

4. 2

The rate constant of the reaction A $\to$ B is 0.6 x 10^-3 molar per second. If the

concentration of A is 5 M then concentration of B after 20 min is

1. 1.08 M

2. 3.60 M

3. 0.36 M

4. 0.72 M

If the rate of reaction doubles when the temperature is raised from 20 °C to 35 °C, then the activation energy for the reaction will be :
(R = 8.314 J mol^-1 K^-1)

1. 342 kJ mol^-1

2. 269 kJ mol^-1

3. 34.7 kJ mol^-1

4. 15.1 kJ mol^-1

A reaction having equal energies of activation for forward and reverse reactions has

1. $∆$S = 0

2. $∆$G = 0

3. $∆$H = 0

4. $∆$H = $∆$G = $∆$S = 0

In a reaction, A+B $\stackrel{ }{\to }$ Product, rate is doubled when the concentration of B is

doubled, and rate increases by a factor of 8 when the concentrations of both the

reactants (A and B) are doubled. Rate law for the reaction can be written as

1. Rate = k[A][B]²

2. Rate = k[A²][B²]

3. Rate = k[A][B]

4. Rate = k[A]² [B]

In a zero order reaction for every 10° rise of temperature, the rate is doubled. If the

temperature is increased from 10°C to 100°C, the rate of the reaction will become

1. 256 times

2. 512 times

3. 64 times

4. 128 times

Which one of the following statements for the order of a reaction is incorrect?

1. Order is not influenced by stiochiometric coefficient of the reactants.

2. Order of reaction is sum of power to the concentration terms of reactants to express the rate of reaction.

3. Order of reaction is always whole number.

4. Order can be determined only experimentally.