
Concept explainers
(a)
Interpretation:
If half-life of a radionuclide is 6.0 hr, then how much fraction of the radionuclide will be present undecayed after 12 hr has to be calculated.
Concept Introduction:
Radioactive nuclides undergo disintegration by emission of radiation. All the radioactive nuclide do not undergo the decay at a same rate. Some decay rapidly and others decay very slowly. The nuclear stability can be quantitatively expressed by using the half-life.
The time required for half quantity of the radioactive substance to undergo decay is known as half-life. It is represented as
The equation that relates amount of decayed radioactive material, amount of undecayed radioactive material and the time elapsed can be given as,
(a)

Answer to Problem 11.25EP
Fraction of radionuclide that will remain after 12 hr is ¼.
Explanation of Solution
Half-life of the radionuclide is given as 6.0 hr. The number of half-lives can be calculated as shown below,
The fraction of nuclide that remains after 12 hr is calculated as shown below,
The fraction of sample that remains after 12 hr is calculated as ¼.
The fraction of the radionuclide sample that remains after 12 hr is calculated.
(b)
Interpretation:
If half-life of a radionuclide is 6.0 hr, then how much fraction of the radionuclide will be present undecayed after 36 hr has to be calculated.
Concept Introduction:
Radioactive nuclides undergo disintegration by emission of radiation. All the radioactive nuclide do not undergo the decay at a same rate. Some decay rapidly and others decay very slowly. The nuclear stability can be quantitatively expressed by using the half-life.
The time required for half quantity of the radioactive substance to undergo decay is known as half-life. It is represented as
The equation that relates amount of decayed radioactive material, amount of undecayed radioactive material and the time elapsed can be given as,
(b)

Answer to Problem 11.25EP
Fraction of radionuclide that will remain after 36 hr is 1/64.
Explanation of Solution
Half-life of the radionuclide is given as 6.0 hr. The number of half-lives can be calculated as shown below,
The fraction of nuclide that remains after 36 hr is calculated as shown below,
The fraction of sample that remains after 36 hr is calculated as 1/64.
The fraction of the radionuclide sample that remains after 36 hr is calculated.
(c)
Interpretation:
If half-life of a radionuclide is 6.0 hr, then how much fraction of the radionuclide will be present undecayed after 3 half-lives has to be calculated.
Concept Introduction:
Radioactive nuclides undergo disintegration by emission of radiation. All the radioactive nuclide do not undergo the decay at a same rate. Some decay rapidly and others decay very slowly. The nuclear stability can be quantitatively expressed by using the half-life.
The time required for half quantity of the radioactive substance to undergo decay is known as half-life. It is represented as
The equation that relates amount of decayed radioactive material, amount of undecayed radioactive material and the time elapsed can be given as,
(c)

Answer to Problem 11.25EP
Fraction of radionuclide that will remain after 3 half-lives is 1/8.
Explanation of Solution
Given number of half-lives is 3 half-lives.
The fraction of nuclide that remains after 3 half-lives is calculated as shown below,
The fraction of sample that remains after 3 half-lives is calculated as 1/8.
The fraction of the radionuclide sample that remains after 3 half-lives is calculated.
(d)
Interpretation:
If half-life of a radionuclide is 6.0 hr, then how much fraction of the radionuclide will be present undecayed after 6 half-lives has to be calculated.
Concept Introduction:
Radioactive nuclides undergo disintegration by emission of radiation. All the radioactive nuclide do not undergo the decay at a same rate. Some decay rapidly and others decay very slowly. The nuclear stability can be quantitatively expressed by using the half-life.
The time required for half quantity of the radioactive substance to undergo decay is known as half-life. It is represented as
The equation that relates amount of decayed radioactive material, amount of undecayed radioactive material and the time elapsed can be given as,
(d)

Answer to Problem 11.25EP
Fraction of radionuclide that will remain after 6 half-lives is 1/64.
Explanation of Solution
Given number of half-lives is 6 half-lives.
The fraction of nuclide that remains after 6 half-lives is calculated as shown below,
The fraction of sample that remains after 6 half-lives is calculated as 1/64.
The fraction of the radionuclide sample that remains after 6 half-lives is calculated.
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Chapter 11 Solutions
General, Organic, and Biological Chemistry Seventh Edition
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- Provide the reasonable steps to achieve the following synthesis.arrow_forwardWhen anisole is treated with excess bromine, the reaction gives a product which shows two singlets in 1H NMR. Draw the product.arrow_forward(ii) Draw a reasonable mechanism for the following reaction: CI NaOH heat OH (hint: SNAr Reaction) :arrow_forward
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