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Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]
- a)0.0075 M
- b)0.06 M
- c)0.03 M
- d)0.015 M
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
Half life of a first order reaction is 4 s and the initial concentrati...
t1/2 = 4 s T = 16
where Å = initial concentration & A = concentration left after time t
Most Upvoted Answer
Half life of a first order reaction is 4 s and the initial concentrati...
Given information:
- Half-life of a first-order reaction = 4 s
- Initial concentration of reactants = 0.12 M
- Time elapsed = 16 s
To find:
- Concentration of reactant left after 16 s
Solution:
1. We know that the half-life (t1/2) of a first-order reaction is given by the equation:
t1/2 = ln(2)/k
where k is the rate constant of the reaction.
2. Rearranging the equation, we get:
k = ln(2)/t1/2
3. Substituting the given t1/2 value of 4 s, we get:
k = ln(2)/4
k = 0.173 s^-1
4. The rate law for a first-order reaction is given by the equation:
Rate = k[A]
where [A] is the concentration of the reactant.
5. Integrating the rate law equation, we get:
ln([A]t/[A]0) = -kt
where [A]t is the concentration of the reactant at time t, and [A]0 is the initial concentration of the reactant.
6. Substituting the given values of k, [A]0, and t = 16 s, we get:
ln([A]16/0.12) = -0.173 x 16
ln([A]16/0.12) = -2.768
[A]16/0.12 = e^-2.768
[A]16 = 0.0075 M
7. Therefore, the concentration of the reactant left after 16 s is 0.0075 M.
Answer: Option A (0.0075 M)
- Half-life of a first-order reaction = 4 s
- Initial concentration of reactants = 0.12 M
- Time elapsed = 16 s
To find:
- Concentration of reactant left after 16 s
Solution:
1. We know that the half-life (t1/2) of a first-order reaction is given by the equation:
t1/2 = ln(2)/k
where k is the rate constant of the reaction.
2. Rearranging the equation, we get:
k = ln(2)/t1/2
3. Substituting the given t1/2 value of 4 s, we get:
k = ln(2)/4
k = 0.173 s^-1
4. The rate law for a first-order reaction is given by the equation:
Rate = k[A]
where [A] is the concentration of the reactant.
5. Integrating the rate law equation, we get:
ln([A]t/[A]0) = -kt
where [A]t is the concentration of the reactant at time t, and [A]0 is the initial concentration of the reactant.
6. Substituting the given values of k, [A]0, and t = 16 s, we get:
ln([A]16/0.12) = -0.173 x 16
ln([A]16/0.12) = -2.768
[A]16/0.12 = e^-2.768
[A]16 = 0.0075 M
7. Therefore, the concentration of the reactant left after 16 s is 0.0075 M.
Answer: Option A (0.0075 M)
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Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? for Class 12 2025 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer?.
Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? for Class 12 2025 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer?.
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Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of Half life of a first order reaction is 4 s and the initial concentration of the reactants is 0.12 M.The concentration of the reactant left after 16 s is [1999]a)0.0075 Mb)0.06 Mc)0.03 Md)0.015 MCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
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