The correct expression for the 3/4th life of a first-order reaction is:
\(1 .  \frac{k}{2 . 303} log \frac{4}{3}\)
\(2 .  \frac{2 . 303}{k} log \frac{3}{4}\)
\(3 .  \frac{2 . 303}{k} log\) \(4\)
\(4 .  \frac{2 . 303}{k}\) \(log\) \(3\)$\mathrm{}$

From the plot of log k vs 1/T, following parameter can be calculated:

1. Activation energy.

2. Rate constant of reaction .

3. Order of reaction.

4. Activation energy as well as the frequency factor.

For an endothermic reaction, where ΔH represents the enthalpy of the reaction in kJ/mol, the minimum value for the energy of activation will be

1. Less than ΔH

2. Zero

3. More than ΔH

4. Equal to ΔΗ

In the formation or sulphur trioxide by the contact process,

2SO₂(g) + O₂(g) $\to$2SO₃(g)

The rate of reaction is expressed as $\frac{\mathrm{d}\left[{\mathrm{O}}_2\right]}{\mathrm{dt}}$= 2.5×10^–4 mol L^–1 sec^–1. The rate disappearance of SO₂ will be

1. 5.0×10^–4 mol L^–1sec^–1

2. 2.5×10^–4 mol L^–1sec^–1

3. 3.75×10^–4 mol L^-1sec^–1

4. 50.0×10^–4 mol L^–1sec^–1

A first order reaction complete 40% in 20 minutes. In how much time it is completed 90% of its original amount?

1. 45 min

2. 60 min 

3. 75 min

4. 90 min

The dissociation of H₂O₂ is a first order reaction. The half life for '16 V H₂O₂ is 30 min, calculate the time at which the solution is 1V H₂O₂ ?

(1) 120 min.

(2) 90 min.

(3) 60 min.

(4) 150 min.

If the activation energy is 65 kJ then the reaction at 25°C is .......times fast as compared to 0°C :-

1. 2 times

2. 5 times

3. 11 times

4. 16 times

When temperature is increased from 27$°$C to 127$°$C, rate of reaction becomes doubled, then E_a will be?

1. 1.66 kcal.

2. 3.32 kcal.

3. 5.33 kcal.

4. 6.64 kcal.

If 2M, 1L solution of acetic acid is added to 3M, 1L ethyl alcohol then the following elementary reaction takes place.

CH₃COOH + C₂H₅OH $\to$ CH₃COOC₂H₅ + H₂0

If each solution is diluted by 1 litre then the initial rate becomes how many times:-

(1) 4

(2) 2

(3) 0.5

(4) 0.25

For a certain reaction, 10% of the reactant dissociates in 1 hour, 20% of the reactant dissociates in 2 hours, 30% of the reactant dissociates in 3 hours. Then the units of the rate constant is:-

(1) hour^-1

(2) mol L^-1 hr^-1

(3) mol L^-1 sec^-1

(4) mol L sec^-1