Advertisements
Advertisements
प्रश्न
Define order of reaction with suitable examples.
उत्तर
The order or overall order of the chemical reaction is given as the sum of powers of the concentration terms in the rate law expression.
For the reaction,
aA + bB → cC + dD
If the rate of the reaction is given as
rate = k[A]x [B]y.
Then, the sum x + y gives overall order of the reaction.
e.g. For the reaction
H2(g) + I2(g) → 2HI(g) is
rate = k[H2][I2].
The reaction is of first-order in H2 and I2 each and hence overall order is second order.
For the reaction,
2H2O2(g) → 2H2O(l) + O2(g)
Experimentally determined rate law is rate = k[H2O2].
The reaction is of first-order in H2O2 and hence, the overall order is first order.
APPEARS IN
संबंधित प्रश्न
Choose the most correct option.
The order of the reaction for which the units of the rate constant are mol dm-3 s-1 is _______.
Choose the most correct option.
The rate constant for the reaction \[\ce{2N2O5_{(g)} -> 2N2O4_{(g)} + O2_{(g)}}\] is `4.98 xx 10^-4 "s"^-1`. The order of reaction is _____________.
The time required for 90% completion of a certain first-order reaction is t. The time required for 99.9% completion will be _________.
Choose the most correct option.
Slope of the graph ln[A]t versus t for first-order reaction is _________.
Choose the most correct option.
The reaction, \[\ce{3ClO- -> ClO^-3 + 2Cl-}\] occurs in two steps,
(i) \[\ce{2ClO- -> ClO^-2}\]
(ii) \[\ce{ClO^-2 + ClO- -> ClO^-_3 + Cl-}\]
The reaction intermediate is _______.
Choose the most correct option.
The elementary reaction \[\ce{O3_{(g)} + O_{(g)} -> 2O2_{(g)}}\] is ___________.
Choose the most correct option.
For an endothermic reaction, X ⇌ Y. If Ef is the activation energy of the forward reaction and Er that for the reverse reaction, which of the following is correct?
Answer the following in one or two sentences.
For the reaction, \[\ce{CH3Br_{(aq)} + OH^{-}_{(aq)} -> CH3OH^{\ominus}_{(aq)} + Br^{\ominus}_{(aq)}}\], rate law is rate = \[\ce{k[CH3Br][OH^\ominus]}\]
How does reaction rate changes if \[\ce{[OH^\ominus]}\] is decreased by a factor of 5?
Answer the following in brief.
For the reaction 2A + B → products, find the rate law from the following data.
| [A]/M | [B]/M | rate/M s-1 |
| 0.3 | 0.05 | 0.15 |
| 0.6 | 0.05 | 0.30 |
| 0.6 | 0.2 | 1.20 |
For the reaction \[\ce{2NO_{(g)} + 2H_{2(g)} -> N_{2(g)} + 2H2O_{(g)}}\],
The rate law is, rate = k[NO]2 [H2].
What is the overall order of reaction?
A reaction occurs in the following steps:
Step 1: \[\ce{NO_{2(g)} + F_2 -> NO2F_{(g)} + F_{(g)}}\] (slow)
Step 2: \[\ce{F_{(g)} + NO_{2(g)} -> NO_2F}\] (Fast)
- Write the equation of overall reaction.
- Write the rate law.
- Identify reaction intermediate.
The rate constant of a first order reaction whose half-life is 480 seconds, is ____________.
For the non-stoichiometric reaction
\[\ce{2A + B -> C + D}\], the following kinetic data were obtained in three separate experiments, all at 298 K.
| Initial concentration (A) |
Initial concentration (B) |
Initial rate of formation of C (mol dm−3 s−1) |
| 0.1 M | 0.1 M | 1.2 × 10−3 |
| 0.1 M | 0.2 M | 1.2 × 10−3 |
| 0.2 M | 0.1 M | 2.4 × 10−3 |
The rate law for the formation of C is:
A gaseous hypothetical chemical equation \[\ce{2A ⇌ 4B + C}\] is carried out in a closed vessel. The concentration of B is found to increase by 5 × 10−3 mol dm−3 in 10 second. The rate of ____________.
The rate law for a reaction between the substances A and B is given by, rate = k[A]n [B]m. On halving the concentration of A and doubling the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as ____________.
For a chemical reaction rate law is, rate = k[A]2[B]. If [A] is doubled at constant [B], the rate of reaction ______.
The order of the reaction occurring by following mechanism should be:
(i) \[\ce{A2 + B2 -> AB2 + A (slow)}\]
(ii) \[\ce{A + B2 -> AB2 (fast)}\]
Consider the reaction \[\ce{2A + 2B -> C + 2D}\], if concentration of A is doubled at constant [B], rate increases by a factor 4. If concentration B is doubled at constant [A] the rate is doubled. Rate law of the reaction is ____________.
In the reaction, \[\ce{N2 + 3H2 -> 2NH3}\], the rate of disappearance of H2 is 0.02 Mis. The rate of appearance of NH3 is ______.
What is the order of reaction for decomposition of gaseous acetaldehyde?
For the reaction \[\ce{2A + B -> 3C + D}\], which among the following is NOT the correct rate law expression?
For the reaction \[\ce{4NH3 + 5O2 -> 4NO + 6H2O}\], the rate of disappearance of NH3 is 3.6 × 10-3 M/s. What is the rate of formation of water?
The correct order of raaii of F, F-, O and O2- is ______.
Write the rate law for the following reaction:
A reaction that is zero order in A and second order in B.
Write the rate law for the following reaction:
A reaction that is second order in NO and first order in Br2.
For a chemical reaction A → 7 products, the rate of reaction doubles when the concentration of A is increased by a factor 4. The order of the reaction is ______.
