The rate constant (in mol L⁻¹ s⁻¹) for a zero-order reaction with an initial concentration of 0.02 M and a half-life of 100 seconds is:
1. \(1.0 \times 10^{-4}\)
2. \(2.0 \times 10^{-4}\)
3. \(2.0 \times 10^{-3}\)
4. \(1.0 \times 10^{-2}\)
The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation, k = Ae-Ea/RT . Activation energy Ea of the reaction can be calculated by plotting :
(1) log vs 1 / log T
(2) k vs T
(3) k vs 1 / log T
(4) log k vs 1 / T
If the rate of the reaction is equal to the rate constant, the order of the reaction is :
(1) 3
(2) 0
(3) 1
(4) 2
3A B + C
It would be a zero order reaction when :
(1) The rate of reaction is proportional to square of concentration of A
(2) The rate of reaction remains same at any concentration of A
(3) The rate remains unchanged at any concentration of B and C
(4) The rate of reaction doubles if concentration of B is increased to double.
The activation energy for a simple chemical reaction
A B is Ea in the forward direction.
The activation energy for the reverse reaction:
1. Can be less than or greater than Ea
2. Is always double of Ea
3. Is negative of Ea
4. Is always less than Ea
For a chemical reaction product, the postulated mechanism of the reaction is as follows.
\(E_{a_{1}} = 180 \ kJ \ mol^{-1}, \)
\( E_{a_{2}} = 90 \ kJ \ mol^{-1}, \)
\( E_{a_{3}} = 40 \ kJ \ mol^{-1}\)
then overall activation energy for the reaction given above is
1. 70 kJ mol-1
2. -10 kJ mol-1
3. 310 kJ mol-1
4. 130 kJ mol-1
1. Pseudo-first-order reaction
2. First-order reaction
3. Second order reaction
4. Third-order reaction
What is the rate equation for reaction 2A+ B C if the order of the reaction is zero ?
1.
2.
3.
4. None of these
For a certain reaction large fraction of molecules have energy more than the threshold energy, yet why the rate of reaction is very slow.It is due to improper:
1. Orientation of colliding molecules.
2. Energy of colliding molecules.
3. Volume of colliding molecules.
4. Entropy of colliding molecules.
For a general reaction A B, the plot of the concentration of A vs. time is given in the figure.
The slope of the curve will be:
1. | -k | 2. | -k/2 |
3. | -k2 | 4. | -k/3 |