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Half-life period of a second order reaction is A: independent of the concentration B: directly proportional to the initial conc C: inversely proportional to conc. D: directly proportional to the conc.?
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Half-life period of a second order reaction is A: independent of the c...
**Half-life period of a second-order reaction**

The half-life period of a reaction is defined as the time it takes for the concentration of a reactant to decrease by half. In a second-order reaction, the rate of the reaction is directly proportional to the square of the concentration of one or both of the reactants. The half-life period of a second-order reaction can be determined by considering the rate equation and understanding the relationship between concentration and time.

**Rate equation of a second-order reaction**

For a second-order reaction, the rate equation can be written as:

Rate = k[A]^2

where [A] represents the concentration of the reactant A and k is the rate constant. The rate constant k is specific to a particular reaction and is determined experimentally.

**Explanation of the options**

A: Independent of the concentration
The half-life period of a second-order reaction is not independent of the concentration. The rate of the reaction is directly proportional to the square of the concentration, as shown in the rate equation. Hence, the concentration does affect the half-life period.

B: Directly proportional to the initial concentration
The half-life period of a second-order reaction is not directly proportional to the initial concentration. The rate of the reaction depends on the concentration at any given time, not just the initial concentration. As the reaction proceeds and the concentration decreases, the rate of the reaction also changes.

C: Inversely proportional to concentration
The half-life period of a second-order reaction is not inversely proportional to the concentration. In a second-order reaction, the rate of the reaction is directly proportional to the square of the concentration, as shown in the rate equation. Therefore, as the concentration decreases, the rate of the reaction decreases, resulting in a longer half-life period.

D: Directly proportional to the concentration
The correct answer is D. The half-life period of a second-order reaction is directly proportional to the concentration. This can be understood by rearranging the rate equation:

Rate = k[A]^2

Rearranging for time, we get:

t = 1/(k[A]^2)

As the concentration increases, the denominator of the equation increases, resulting in a smaller value for time (t). Therefore, the half-life period is directly proportional to the concentration.

In conclusion, the half-life period of a second-order reaction is directly proportional to the concentration. As the concentration decreases, the half-life period increases, and vice versa.
Community Answer
Half-life period of a second order reaction is A: independent of the c...
Inversely proportional to initial concentration.....
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Read the passage given below and answer the following questions:The rate of a reaction, which may also be called its velocity or speed, can be defined with relation to the concentration of any of the reacting substances, or to that of any product of the reaction. If the species chosen is a reactant which has a concentration c at time t the rate is - dc/dt, while the rate with reference to a product having a concentration x at time t is dx/dt. Any concentration units may be used for expressing the rate; thus, if moles per liter are employed for concentration and seconds for the time, the units for the rate are moles litre–1sec–1. For gas reactions pressure units are sometimes used in place of concentrations, so that legitimate units for the rate would be (mm. Hg) sec–1 and atm. sec–1 The order of a reaction concerns the dependence of the rate upon the concentrations of reacting substances; thus, if the rate is found experimentally to be proportional to the ath power of the concentration of one of the reactants A, to the both power of the concentration of a second reactant B, and so forth, via., rate = k CAα CAβ the over-all order of the reaction is simply n = α + β + ----- (2) Such a reaction is said to be of the αth order with respect to the substance A, the βth order with respect to B.In the following questions, a statement of Assertion followed by a statement of Reason is given. Choose the correct answer out of the following choices on the basis of the above passage.Assertion: The unit of k is independent of order of reaction.Reason: The unit of k is moles L–1s–1.

Read the passage given below and answer the following questions:The rate of a reaction, which may also be called its velocity or speed, can be defined with relation to the concentration of any of the reacting substances, or to that of any product of the reaction. If the species chosen is a reactant which has a concentration c at time t the rate is - dc/dt, while the rate with reference to a product having a concentration x at time t is dx/dt. Any concentration units may be used for expressing the rate; thus, if moles per liter are employed for concentration and seconds for the time, the units for the rate are moles litre–1sec–1. For gas reactions pressure units are sometimes used in place of concentrations, so that legitimate units for the rate would be (mm. Hg) sec–1 and atm. sec–1 The order of a reaction concerns the dependence of the rate upon the concentrations of reacting substances; thus, if the rate is found experimentally to be proportional to the ath power of the concentration of one of the reactants A, to the both power of the concentration of a second reactant B, and so forth, via., rate = k CAα CAβ the over-all order of the reaction is simply n = α + β + ----- (2) Such a reaction is said to be of the αth order with respect to the substance A, the βth order with respect to B.In the following questions, a statement of Assertion followed by a statement of Reason is given. Choose the correct answer out of the following choices on the basis of the above passage.Assertion: Rate of reaction is a measure of change in concentration of reactant with respect to time.Reason: Rate of reaction is a measure of change in concentration of product with respect to time.

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Half-life period of a second order reaction is A: independent of the concentration B: directly proportional to the initial conc C: inversely proportional to conc. D: directly proportional to the conc.?
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Half-life period of a second order reaction is A: independent of the concentration B: directly proportional to the initial conc C: inversely proportional to conc. D: directly proportional to the conc.? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about Half-life period of a second order reaction is A: independent of the concentration B: directly proportional to the initial conc C: inversely proportional to conc. D: directly proportional to the conc.? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Half-life period of a second order reaction is A: independent of the concentration B: directly proportional to the initial conc C: inversely proportional to conc. D: directly proportional to the conc.?.
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