The rate constant for a first order reaction is . The time required to reduce 2.0 g of the reactant to 0.2 g is:
1. | 200 s | 2. | 500 s |
3. | 1000 s | 4. | 100 s |
An increase in the concentration of the reactants of a reaction leads to a change in:
1. | Heat of reaction | 2. | Threshold energy |
3. | Collision frequency | 4. | Activation energy |
The half-life for a zero-order reaction having 0.02 M initial concentration of reactant is 100 s. The rate constant (in mol L–1 s–1) for the reaction is:
1.
2.
3.
4.
What does ZAB represent in the collision theory of chemical reactions?
1. | The fraction of molecules with energies greater than Ea |
2. | The collision frequency of reactants, A and B |
3. | Steric factor |
4. | The fraction of molecules with energies equal to Ea |
For a reaction, activation energy and the rate constant at 200 K is 1.6 . The rate constant at 400K will be [Given that gas constant, R=8.314 J ]
1. 3.2 × 104 s-1
2. 1.6 × 106s-1
3. 1.6 × 103 s-1
4. 3.2 × 106 s-1
A first-order reaction has a rate constant of 2.303 . The time required for 40 g of this reactant to reduce to 10 g will be
[Given that ]
1. | 230.3 s | 2. | 301 s |
3. | 2000 s | 4. | 602 s |
The unit of rate constant for a zero-order reaction is:
1.
2.
3.
4.
The half-life of a certain enzyme catalysed reaction is 138 s, that follow the 1st order kinetics. The time required for the concentration of the substance to fall from 1.28 mg L–1 to 0.04 mg L–1, is:
1. 276 s
2. 414 s
3. 552 s
4. 690 s
The rate of the reaction can be written in three ways:
The relationship between k and k′ and between
k and k′′ are-
1. k′ = k, k′′= k
2. k′= 2k; k′′= k
3. k′= 2k, k′′= k/2
4. k′ = 2k; k′′= 2k
The rate of the reaction
2NO + Cl2 → 2NOCl is given by the rate equation
rate = k[NO]2[Cl2]
The value of the rate constant can be increased by:
1. Increasing the concentration of NO
2. Increasing the concentration of Cl2
3. Increasing the temperature
4. All of the above