In the presence of a catalyst, the heat evolved or absorbed during the reaction:
1. Increases.
2. Decreases.
3. Remains unchanged.
4. May increase or decrease.
The activation energy of a chemical reaction can be calculated by:
1. Determining the rate constant at standard temperature.
2. Determining the rate constant at two temperatures.
3. Determining probability of collision.
4. Using the catalyst.
The correct statement based on the graph below is:
1. | The activation energy of the forward reaction is E1 + E2 and the product is less stable than reactant. |
2. | The activation energy of the forward reaction is E1 + E2 and the product is more stable than the reactant. |
3. | The activation energy of both forward and backward reaction is E1 + E2 and reactant is more stable than the product. |
4. | The activation energy of the backward reaction is E1 and the product is more stable than reactant. |
Consider the first-order gas-phase decomposition reaction given below.
A(g) → B(g) + C(g)
The initial pressure of the system before the decomposition of A was . After the lapse of time t, the total pressure of the system increased by X units and became . The rate constant k for the reaction is:
1.
2.
3.
4.
The correct graphical representation of relation between ln k and 1/T is:
1. | 2. | ||
3. | 4. |
Consider the Arrhenius equation given below and choose the correct option:
1. | Rate constant increases exponentially with increasing activation energy and decreasing temperature. |
2. | Rate constant decreases exponentially with increasing activation energy and increasing temperature. |
3. | Rate constant increases exponentially with decreasing activation energy and decreasing temperature. |
4. | Rate constant increases exponentially with decreasing activation energy and increasing temperature. |
True statement among the following is:
1. | The rate of a reaction decreases with the passage of time as the concentration of reactants decreases. |
2. | The rate of a reaction is the same at any time during the reaction. |
3. | The rate of a reaction is independent of temperature change. |
4. | The rate of a reaction decreases with an increase in the concentration of the reactants. |
The correct expression for the rate of reaction given below is:
\(5 \mathrm{Br}^{-}(\mathrm{aq})+\mathrm{BrO}_3^{-}(\mathrm{aq})+6 \mathrm{H}^{+}(\mathrm{aq}) \rightarrow 3 \mathrm{Br}_2(\mathrm{aq})+3 \mathrm{H}_2 \mathrm{O}(\mathrm{l})\)
1. | \(\frac{\Delta\left[B r^{-}\right]}{\Delta t}=5 \frac{\Delta\left[H^{+}\right]}{\Delta t} \) | 2. | \(\frac{\Delta\left[\mathrm{Br}^{-}\right]}{\Delta t}=\frac{6}{5} \frac{\Delta\left[\mathrm{H}^{+}\right]}{\Delta t} \) |
3. | \(\frac{\Delta[\mathrm{Br^-}]}{\Delta t}=\frac{5}{6} \frac{\Delta\left[\mathrm{H}^{+}\right]}{\Delta t} \) | 4. | \(\frac{\Delta\left[\mathrm{Br}^{-}\right]}{\Delta t}=6 \frac{\Delta\left[\mathrm{H}^{+}\right]}{\Delta t}\) |
The correct representation of an exothermic reaction is:
1. | 2. | ||
3. | 4. | Both 1 and 2 |
Rate law for the reaction \(A+2 B \rightarrow C\) is found to be
Rate = k[A][B]
If the concentration of reactant 'B' is doubled, keeping the concentration of A constant, then the value of the rate of the reaction will be:
1. | The same. | 2. | Doubled. |
3. | Quadrupled. | 4. | Halved. |