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Nuclear Chemistry : Radioactive Decay

Question 1
A radioisotope decays to give an alpha particle and Pb-208. What was the original element?

Se
Bi
Po
Hg
Rn

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Question 2
Sulfur-35 decays by beta emission. The decay product is ________.

P
S
Si
35-Cl
37- Cl

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Question 3
Carbon-11 is a radioactive isotope of carbon. Its half-life is 20.3 minutes. What fraction of the initial number of C-11 atoms in a sample will remain after 81 minutes?

1/16
1/4
1/2
1/32
1/8

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Question 4
Po-208 is an alpha emitter with a half-life of 2.90 years. How many mg of polonium from an original sample of 2.0 mg will remain after 8.0 years?

0.147 mg
0.295 mg
0.725 mg
6.77 mg
1.90 mg

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Question 5
Charcoal found under a stone at Stonehenge, England, has a carbon-14 activity that is 0.60 that of new wood. How old is the charcoal? The half-life of carbon-14 is 5,730 years.

Less than 5,730 years
Between 5,730 and 11,460 years
Between 11,460 and 17,190 years
More than 17,190 years

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Question 6
What role does cadmium metal (Cd) play in a nuclear reactor?

slows down the fission neutrons (moderator)
transfers heat from the reactor to the heat exchanger (primary coolant)
controls chain reaction (control rods)
transfers heat from the condenser to the environment (cooling tower)
undergoes fission (fuel rods)

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Question 7
Which one of the following is the most penetrating of the three types of nuclear radiation?

alpha
beta
gamma

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Question 8
Gamma-rays and X-rays cause radiation damage when they interact with matter by producing ________.

ions and free radicals
isotopes
daughter products
oxidation
reduction

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Question 9
How many neutrons and protons (nucleons) does an atom with the symbol S have?

33
16
49
17
None of the above.

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Question 10
Predict the other product of the following nuclear transformation.

Li + n _____ + He

He
H
H
β
H

Solution Summary

Nuclear chemistry and radioactive decay problems are solved. The solution is detailed and well presented.

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