For kinetic study of the reaction of iodide ion with \(H _2 O _2\) at room temperature :
(A) Always use freshly prepared starch solution
(B) Always keep the concentration of sodium thiosulphate solution less than that of \(KI\) solution
(C) Record the time immediately after the appearance of blue colour
(D) Record the time immediately before the appearance of blue colour
(E) Always keep the concentration of sodium thiosulphate solution more than that of \(KI\) solution Choose the correct answer from the options given below :
(A) Always use freshly prepared starch solution
(B) Always keep the concentration of sodium thiosulphate solution less than that of \(KI\) solution
(C) Record the time immediately after the appearance of blue colour
(D) Record the time immediately before the appearance of blue colour
(E) Always keep the concentration of sodium thiosulphate solution more than that of \(KI\) solution Choose the correct answer from the options given below :
- (A), (B), (C) only
- (A), (D), (E) only
- (D), (E) only
- (A), (B), (E) only
The Correct Option is A
Solution and Explanation
The correct option is (A): (A), (B), (C) only
Top Questions on Chemical Kinetics
- Drug X becomes ineffective after 50% decomposition. The original concentration of drug in a bottle was 16 mg/mL which becomes 4 mg/mL in 12 months. The expiry time of the drug in months is ____ . Assume that the decomposition of the drug follows first order kinetics.
- JEE Main - 2025
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- In a first order decomposition reaction, the time taken for the decomposition of reactant to one fourth and one eighth of its initial concentration are $ t_1 $ and $ t_2 $ (s), respectively. The ratio $ t_1 / t_2 $ will be:
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- Consider the following statements related to temperature dependence of rate constants. Identify the correct statements,
A. The Arrhenius equation holds true only for an elementary homogeneous reaction.
B. The unit of A is same as that of k in Arrhenius equation.
C. At a given temperature, a low activation energy means a fast reaction.
D. A and Ea as used in Arrhenius equation depend on temperature.
E. When Ea >> RT. A and Ea become interdependent.
Choose the correct answer from the options given below :- JEE Main - 2025
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- Half-life of zero-order reaction $ A \to $ product is 1 hour, when initial concentration of reaction is 2.0 mol L$^{-1}$. The time required to decrease concentration of A from 0.50 to 0.25 mol L$^{-1}$ is:
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- Chemistry
- Chemical Kinetics
Consider the following plots of log of rate constant $ k (log k)$ vs $ \frac{1}{T} $ for three different reactions. The correct order of activation energies of these reactions is:
Choose the correct answer from the options given below:- JEE Main - 2025
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- Chemical Kinetics
Questions Asked in JEE Main exam
Given below are two statements:
Statement (I):
are isomeric compounds.
Statement (II):
are functional group isomers.
In the light of the above statements, choose the correct answer from the options given below:- JEE Main - 2025
- Isomerism
- Let \( [x] \) denote the greatest integer function, and let \( m \) and \( n \) respectively be the numbers of the points, where the function \( f(x) = [x] + |x - 2| \), \( -2<x<3 \), is not continuous and not differentiable. Then \( m + n \) is equal to:
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The effect of temperature on the spontaneity of reactions are represented as: Which of the following is correct?
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- The electric field of an electromagnetic wave in free space is \[ \vec{E} = 57 \cos \left[7.5 \times 10^6 t - 5 \times 10^{-3} (3x + 4y)\right] \left( 4\hat{i} - 3\hat{j} \right) \, \text{N/C}. \] The associated magnetic field in Tesla is:
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- Total number of non-bonded electrons present in \( \text{NO}_2 \); ion based on Lewis theory is:
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Concepts Used:
Chemical Kinetics
Chemical kinetics is the description of the rate of a chemical reaction. This is the rate at which the reactants are transformed into products. This may take place by abiotic or by biological systems, such as microbial metabolism.
Rate of a Chemical Reaction:
The speed of a reaction or the rate of a reaction can be defined as the change in concentration of a reactant or product in unit time. To be more specific, it can be expressed in terms of: (i) the rate of decrease in the concentration of any one of the reactants, or (ii) the rate of increase in concentration of any one of the products. Consider a hypothetical reaction, assuming that the volume of the system remains constant. R → P
Read More: Chemical Kinetics MCQ
Factors Affecting The Reaction Rate:
- The concentration of Reactants - According to collision theory, which is discussed later, reactant molecules collide with each other to form products.
- Nature of the Reactants - The reaction rate also depends on the types of substances that are reacting.
- Physical State of Reactants - The physical state of a reactant whether it is solid, liquid, or gas can greatly affect the rate of change.
- Surface Area of Reactants - When two or more reactants are in the same phase of fluid, their particles collide more often than when either or both are in the solid phase or when they are in a heterogeneous mixture. In a heterogeneous medium, the collision between the particles occurs at an interface between phases. Compared to the homogeneous case, the number of collisions between reactants per unit time is significantly reduced, and so is the reaction rate.
- Temperature - If the temperature is increased, the number of collisions between reactant molecules per second. Increases, thereby increasing the rate of the reaction.
- Effect Of Solvent - The nature of the solvent also depends on the reaction rate of the solute particles.
- Catalyst - Catalysts alter the rate of the reaction by changing the reaction mechanism.