If the rate of the reaction is equal to the rate constant, the order of the reaction is
A
0
B
1
C
2
D
3
Explanation
As r = k[A]n
if n = 0
r = k[A]0
or r = k thus for zero order reactions rate is equal
to the rate constant.
2
MCQ (Single Correct Answer)
AIPMT 2003
The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation, $$k = A \cdot {e^{ - E{}^ * /RT}}$$. Activation energy (E$$ * $$) of the reaction can be calculated by plotting
A
$$k\,\,vs\,\,T$$
B
$$k\,\,vs\,\,{1 \over {\log T}}$$
C
$$\log \,k\,\,vs\,\,{1 \over T}$$
D
$$\log \,k\,\,vs\,{1 \over {\log T}}$$
Explanation
Arrhenius equation k = $$A{e^{ - {{{E_a}} \over {RT}}}}$$
$$ \Rightarrow $$ log k = log A - $${{{{E_a}} \over {2.303RT}}}$$
Comparing it with equation of straight line i.e.,
y = mx + C
On plotting log k vs $${1 \over T}$$, we get a straight
line, the slope indicates the value of activation
energy.
3
MCQ (Single Correct Answer)
AIPMT 2002
2A $$ \to $$ B + C
It would be a zero order reaction when
A
the rate of reaction is proportional to square of concentration of A
B
The rate of reaction remains same at any concentration of A
C
the rate remains unchanged at any concentration of B and C
D
the rate of reaction doubles if concentrations of B is increased to double.
Explanation
2A $$ \to $$ B + C
If it is zero order reaction r = k [A]o.
i.e the rate
remains same at any concentration
of 'A'. i.e independent upon concentration of A.
4
MCQ (Single Correct Answer)
AIPMT 2001
For the reaction;
2N2O5 $$ \to $$ 4NO2 + O2 rate and rate constant are 1.02 $$ \times $$ 10$$-$$4 and 3.4 $$ \times $$ 10$$-$$5 sec$$-$$1 respectively, then concentration of N2O5 at that time will be