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

For a first order reaction A $\to$ product :

(1)

(2)

(3)

(4) 

Two reactions of the same order have equal Pre-exponential factors but their activation energies differ by 24.9 kJ/mol. Calculate the ratio between the rate constants (K₁/K₂) these reactions at 27°C :

1. 2.2 × 10⁴

2. 1/2 × 10^-4

3. 1/2 × 10⁴

4. 2.2 × 10^-4

The activation energy of a reaction is zero. The rate constant of the reaction is :

1. increases with an increase in temperature

2. decreases with a decrease in temperature

3. decreases with an increase in temperature

4. is nearly independent of temperature

The rate constant of a first order reaction is 10^-3 min^-1 at 27°C. The temperature coefficient of this  reaction is 2. The rate constant at 17°C will be :

(1) 10^-3 min^-1

(2) 5  x 10^-4 min^-1

(3) 2 x 10^-3 min^-1

(4) 10^-2 min^-1