1
MCQ (Single Correct Answer)
The role of a catalyst is to change ̣............ .
A
Gibbs energy of reaction
B
enthalpy of reaction
C
activation energy of reaction
D
equilibrium constant
2
MCQ (Single Correct Answer)
In the presence of a catalyst, the heat evolved or absorbed during the reaction .......... .
A
increases
B
decreases
C
remains unchanged
D
may increase or decrease
3
MCQ (Single Correct Answer)
Activation energy of a chemical reaction can be determined by
A
determining the rate constant at standard temperature
B
determining the rate constant at two temperatures
C
determining probability of collision
D
using catalyst
4
MCQ (Single Correct Answer)
Consider figure and mark the correct option.
A
Activation energy of forward reaction is $E_1+E_2$ and product is less stable than reactant
B
Activation energy of forward reaction is $E_1+E_2$ and product is more stable than reactant
C
Activation energy of both forward and backward reaction is $E_1+E_2$ and reactant is more stable than product
D
Activation energy of backward reaction is $E_1$ and product is more stable than reactant
5
MCQ (Single Correct Answer)
Consider a first order gas phase decomposition reaction given below
$$A(g) \rightarrow B(g)+C(g)$$
The initial pressure of the system before decomposition of $A$ was $p_i$. After lapse of time ' t ' total pressure of the system increased by x units and became ' $\mathrm{p}_{\mathrm{t}}$ '. The rate constant k for the reaction is given as ........... .
A
$k=\frac{2.303}{t} \log \frac{p_i}{p_i-x}$
B
$k=\frac{2.303}{t} \log \frac{p_i}{2 p_i-p_t}$
C
$k=\frac{2.303}{t} \log \frac{p_i}{2 p_i+p_t}$
D
$k=\frac{2.303}{t} \log \frac{p_i}{p_i+x}$