Question 1

A geological sample is found to have a Pb-206/U-238 mass ratio of 0.337/1.00.Assuming there was no Pb-206 present when the sample was formed,how old is it? The half-life of U-238 is 4.5 × 10⁹ years.

Accepted Answer

The answer of A geological sample is found to have...

Question 2

Determine the half-life of a nuclide that loses 38.0% of its mass in 387 hours.

Accepted Answer

The half-life of a radioactive substance is the time it takes for half of the sample to decay. In this case, the nuclide lost 38.0% of its mass, which means that it has 62.0% of its original mass remaining. We can set up an equation using the formula for exponential decay:

0.62 = (1/2)^(t/h)

where t is the time in hours and h is the half-life in hours. Solving for h, we get:

h = t / log2(1/2)

h = t / (-0.693)

h = -1.443t

Plugging in the given values:

0.62 = (1/2)^(387/h)

Taking the log of both sides:

log(0.62) = -387/h * log(2)

h = -387 / (log(0.62) / log(2))

h ≈ 561 hours

Therefore, the half-life of the nuclide is approximately 561 hours.

Question 3

Calculate the mass defect in Mo-96 if the mass of a Mo-96 nucleus is 95.962 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Accepted Answer

The mass defect is calculated by subtracting the actual mass of the nucleus from the sum of the masses of its protons and neutrons. Mo-96 has 42 protons (since Mo is the 42nd element) and 54 neutrons (96 - 42 = 54). The total mass of protons and neutrons is (42 * 1.00728 amu) + (54 * 1.008665 amu) = 42.30576 amu + 54.46811 amu = 96.77387 amu. The mass defect is 96.77387 amu - 95.962 amu = 0.81187 amu, which rounds to 0.812 amu.

Question 4

Fluorine-18 undergoes positron emission with a half-life of 1.10 × 10² minutes.If a patient is given a 248 mg dose for a PET scan,how long will it take for the amount of fluorine-18 to drop to 83 mg? (Assume that none of the fluorine is excreted from the body.)

Accepted Answer

The answer of Fluorine-18 undergoes positron emission with a half-life...

Question 5

The nuclide As-76 has a half-life of 26.0 hours.If a sample of As-76 weighs 344 g,what mass of As-76 remains after 538 minutes?

Accepted Answer

The answer of The nuclide As-76 has a half-life of...

Question 6

Complete the following equation of transmutation. 
14
7 N + 4
2 He ? $\begin{array} { c } 
17 \
8
\end{array}$ O + ________

Accepted Answer

The answer of Complete the following equation of transmutation. 
14
7...

Question 7

The following reaction represents what nuclear process? 
$\begin{array} { l } 
2 \
1
\end{array}$ H + $\begin{array} { l } 
2 \
1
\end{array}$ H ? $\begin{array} { l } 
3 \
2
\end{array}$ He + $\begin{array} { l } 
1 \
0
\end{array}$ n

Accepted Answer

The reaction involves the combination of two hydrogen nuclei (protium) to form a helium nucleus and a neutron. This is the process of nuclear fusion, which powers stars and is a potential source of energy on Earth.

Question 8

The splitting of the uranium atom is called ________.

Accepted Answer

The splitting of the uranium atom is called nuclear fission.

Question 9

Write a nuclear equation to describe the neutron-induced fission of U-235 to form Xe-134 and Sr-100.Determine how many neutrons are produced in the reaction.

Accepted Answer

The nuclear equation is: 
U-235 + n → Xe-134 + Sr-100 + 2n

This reaction produces 2 neutrons, which are released as byproducts of the fission process. Therefore, the answer is E, 2.

Question 10

Complete the following equation of nuclear fusion. 
$\begin{array} { l } 
2 \
1
\end{array}$ H + $\begin{array} { l } 
3 \
1
\end{array}$ H ? 4
2 He + ________

Accepted Answer

The mass number on the left side of the equation is 2+3 = 5, and on the right side it is 4 (2+2). Therefore, one neutron (mass number 1) must be produced to balance the equation.

Question 11

Determine how many neutrons are produced during the neutron-induced fission of 239
94 Pu to form 89
36 Kr and 149
58 Ce.

Accepted Answer

The neutron-induced fission of 23994 Pu produces 2 or 3 neutrons.

Question 12

Calculate the mass defect in Fe-56 if the mass of an Fe-56 nucleus is 55.921 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Accepted Answer

The answer of Calculate the mass defect in Fe-56 if...

Question 13

Determine how many neutrons are produced during the spontaneous fission of 244
95 Am to form I-134 and Mo-107.

Accepted Answer

During the spontaneous fission of 244 95 Am, I-134 and Mo-107 are formed. 
244 95 Am → I-134 + Mo-107 + X(neutrons) 
To find out the number of neutrons produced, we need to balance the equation. 
The atomic number of I-134 is 53 and Mo-107 is 42. 
So, 95 = 53 + 42 + X 
X = 0 
Therefore, no neutrons are produced during the spontaneous fission of 244 95 Am to form I-134 and Mo-107.

Question 14

The combination of two light nuclei to form a heavier nuclei is called ________.

Accepted Answer

Nuclear fusion is the process of combining two light nuclei to form a heavier nucleus. This process releases a large amount of energy, and it is the power source of the sun and other stars. Radioactive cleavage, nuclear fission, and radioactive merge are not valid terms in nuclear physics. The half-life is a term used to describe the decay of radioactive isotopes.

Question 15

Calculate the mass defect in Ni-59 if the mass of a Ni-59 nucleus is 58.69344 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Accepted Answer

The mass of Ni-59 nucleus = 58.69344 amu
Number of protons in Ni-59 = 28 (as the atomic number of Nickel is 28)
Number of neutrons in Ni-59 = 59 - 28 = 31

Total mass of 28 protons = 28 x 1.00728 amu = 28.2 amu
Total mass of 31 neutrons = 31 x 1.008665 amu = 31.3 amu
Therefore, total mass of protons and neutrons = 28.2 + 31.3 = 59.5 amu

Mass defect = (actual mass - total mass of protons and neutrons)
= 58.69344 amu - 59.5 amu
= -0.80656 amu
(Note that the mass defect is negative because the actual mass is less than the total mass of protons and neutrons)

Therefore, the mass defect in Ni-59 = 0.80656 amu

However, the question asks for the mass defect in terms of difference between neutron and proton masses.

Mass of a neutron = 1.008665 amu
Mass of a proton = 1.00728 amu
Mass excess of a neutron = 0.78234 amu (mass of a neutron - mass of a proton)

Mass defect = (number of protons x mass excess of a proton) + (number of neutrons x mass excess of a neutron)
= (28 x 0.78234) + (31 x 0.008315)
= 21.88792 + 0.25797
=0.77902 amu

Therefore, the best answer is B, which is 0.77902 amu.

Question 16

Determine the binding energy of a F-19 nucleus.The F-19 nucleus has a mass of 18.99840325 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Accepted Answer

The total mass of 9 protons and 10 neutrons is:
(9 protons * 1.00728 amu/proton) + (10 neutrons * 1.008665 amu/neutron) = 18.99840325 amu (the mass of F-19 nucleus)

The binding energy can be calculated as:
mass defect * c^2 = (mass of individual nucleons - mass of nucleus) * c^2
mass defect = (9 * 1.00728 amu + 10 * 1.008665 amu - 18.99840325 amu) = 0.09788375 amu

Binding energy = mass defect * 931 MeV/amu = 91.13 MeV = 143 MeV (rounded to the nearest MeV)

Question 17

The following reaction represents what nuclear process? 
$\begin{array} { c } 
235 \
92
\end{array}$ U + $\begin{array} { l } 
1 \
0
\end{array}$ n ? $\begin{array} { c } 
139 \
56
\end{array}$ Ba + 94
36 Kr + 3 $\begin{array} { l } 
1 \
0
\end{array}$ n

Accepted Answer

This reaction represents nuclear fission, where a heavy nucleus (Uranium-235) is split into two lighter nuclei (Barium-139 and Krypton-94) and some neutrons are also released.

Question 18

The age of an ancient tree trunk is estimated using radiocarbon dating.If the trunk has a C-14 decay rate that is 34% of what it is in living plants,how old is the trunk? The half-life of C-14 is 5730 years.

Accepted Answer

We know that the decay rate of C-14 in the ancient trunk is 34% of what it is in living plants. This means that the remaining C-14 is 66% (100% - 34%) of what it would be in a living plant. 
We can use the formula for radioactive decay to find the age of the trunk:

Remaining amount = Initial amount x (1/2)^(t/half-life)

where t is the time that has passed and half-life is the time it takes for half of the initial amount to decay.

Let's use L to represent the remaining amount of C-14 in the trunk (as a fraction of what it would be in a living plant) and let's use I to represent the initial amount of C-14 (also as a fraction of what it would be in a living plant).

We know that L = 0.66I (because the remaining C-14 is 66% of the initial amount). We also know that half-life = 5730 years.

Substituting these values into the formula gives us:

0.66I = I x (1/2)^(t/5730)

Dividing both sides by I gives:

0.66 = (1/2)^(t/5730)

Taking the logarithm of both sides gives:

log(0.66) = (t/5730) x log(1/2)

Solving for t gives:

t = (log(0.66) / log(1/2)) x 5730

Using a calculator gives t ≈ 8.92 × 10^13 seconds, or about 2.83 million years. Since this is closest to answer choice C, we select it as the correct answer.

Question 19

Determine the binding energy of an O-16 nucleus.The O-16 nucleus has a mass of 15.9905 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Accepted Answer

The binding energy of a nucleus can be calculated using the formula: $$BE = \left( Zm_p + Nm_n - M \right) \times 931 \, \text{MeV}$$ where $Z$ is the number of protons, $N$ is the number of neutrons, $m_p$ is the mass of a proton, $m_n$ is the mass of a neutron, $M$ is the mass of the nucleus, and 931 MeV is the energy equivalent of 1 amu. For an O-16 nucleus, $Z = 8$ (since it's oxygen), $N = 8$ (since it's O-16, meaning 16 total nucleons minus 8 protons gives 8 neutrons), $m_p = 1.00728 \, \text{amu}$, $m_n = 1.008665 \, \text{amu}$, and $M = 15.9905 \, \text{amu}$. Plugging these values into the formula gives: $$BE = \left( 8 \times 1.00728 + 8 \times 1.008665 - 15.9905 \right) \times 931 = 128 \, \text{MeV}$$

Question 20

Determine the binding energy per nucleon of a Mg-24 nucleus.The Mg-24 nucleus has a mass of 24.30506.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Accepted Answer

The answer of Determine the binding energy per nucleon of...

Quiz 19: Radioactivity and Nuclear Chemistry

A geological sample is found to have a Pb-206/U-238 mass ratio of 0.337/1.00.Assuming there was no Pb-206 present when the sample was formed,how old is it? The half-life of U-238 is 4.5 × 10⁹ years.

Determine the half-life of a nuclide that loses 38.0% of its mass in 387 hours.

Calculate the mass defect in Mo-96 if the mass of a Mo-96 nucleus is 95.962 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Fluorine-18 undergoes positron emission with a half-life of 1.10 × 10² minutes.If a patient is given a 248 mg dose for a PET scan,how long will it take for the amount of fluorine-18 to drop to 83 mg? (Assume that none of the fluorine is excreted from the body.)

The nuclide As-76 has a half-life of 26.0 hours.If a sample of As-76 weighs 344 g,what mass of As-76 remains after 538 minutes?

Complete the following equation of transmutation. 14 7 N + 4 2 He ? $\begin{array} { c } 17 \\8\end{array}$ O + ________

The following reaction represents what nuclear process? $\begin{array} { l } 2 \\1\end{array}$ H + $\begin{array} { l } 2 \\1\end{array}$ H ? $\begin{array} { l } 3 \\2\end{array}$ He + $\begin{array} { l } 1 \\0\end{array}$ n

The splitting of the uranium atom is called ________.

Write a nuclear equation to describe the neutron-induced fission of U-235 to form Xe-134 and Sr-100.Determine how many neutrons are produced in the reaction.

Complete the following equation of nuclear fusion. $\begin{array} { l } 2 \\1\end{array}$ H + $\begin{array} { l } 3 \\1\end{array}$ H ? 4 2 He + ________

Determine how many neutrons are produced during the neutron-induced fission of 239 94 Pu to form 89 36 Kr and 149 58 Ce.

Calculate the mass defect in Fe-56 if the mass of an Fe-56 nucleus is 55.921 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Determine how many neutrons are produced during the spontaneous fission of 244 95 Am to form I-134 and Mo-107.

The combination of two light nuclei to form a heavier nuclei is called ________.

Calculate the mass defect in Ni-59 if the mass of a Ni-59 nucleus is 58.69344 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Determine the binding energy of a F-19 nucleus.The F-19 nucleus has a mass of 18.99840325 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

The following reaction represents what nuclear process? $\begin{array} { c } 235 \\92\end{array}$ U + $\begin{array} { l } 1 \\0\end{array}$ n ? $\begin{array} { c } 139 \\56\end{array}$ Ba + 94 36 Kr + 3 $\begin{array} { l } 1 \\0\end{array}$ n

The age of an ancient tree trunk is estimated using radiocarbon dating.If the trunk has a C-14 decay rate that is 34% of what it is in living plants,how old is the trunk? The half-life of C-14 is 5730 years.

Determine the binding energy of an O-16 nucleus.The O-16 nucleus has a mass of 15.9905 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Determine the binding energy per nucleon of a Mg-24 nucleus.The Mg-24 nucleus has a mass of 24.30506.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Quiz 19: Radioactivity and Nuclear Chemistry

A geological sample is found to have a Pb-206/U-238 mass ratio of 0.337/1.00.Assuming there was no Pb-206 present when the sample was formed,how old is it? The half-life of U-238 is 4.5 × 109 years.

Determine the half-life of a nuclide that loses 38.0% of its mass in 387 hours.

Calculate the mass defect in Mo-96 if the mass of a Mo-96 nucleus is 95.962 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Fluorine-18 undergoes positron emission with a half-life of 1.10 × 102 minutes.If a patient is given a 248 mg dose for a PET scan,how long will it take for the amount of fluorine-18 to drop to 83 mg? (Assume that none of the fluorine is excreted from the body.)

The nuclide As-76 has a half-life of 26.0 hours.If a sample of As-76 weighs 344 g,what mass of As-76 remains after 538 minutes?

Complete the following equation of transmutation. 14 7 N + 4 2 He ? 178\begin{array} { c } 17 \\8\end{array}178​ O + ________

The following reaction represents what nuclear process? 21\begin{array} { l } 2 \\1\end{array}21​ H + 21\begin{array} { l } 2 \\1\end{array}21​ H ? 32\begin{array} { l } 3 \\2\end{array}32​ He + 10\begin{array} { l } 1 \\0\end{array}10​ n

The splitting of the uranium atom is called ________.

Write a nuclear equation to describe the neutron-induced fission of U-235 to form Xe-134 and Sr-100.Determine how many neutrons are produced in the reaction.

Complete the following equation of nuclear fusion. 21\begin{array} { l } 2 \\1\end{array}21​ H + 31\begin{array} { l } 3 \\1\end{array}31​ H ? 4 2 He + ________

Determine how many neutrons are produced during the neutron-induced fission of 239 94 Pu to form 89 36 Kr and 149 58 Ce.

Calculate the mass defect in Fe-56 if the mass of an Fe-56 nucleus is 55.921 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Determine how many neutrons are produced during the spontaneous fission of 244 95 Am to form I-134 and Mo-107.

The combination of two light nuclei to form a heavier nuclei is called ________.

Calculate the mass defect in Ni-59 if the mass of a Ni-59 nucleus is 58.69344 amu.The mass of a proton is 1.00728 amu and the mass of a neutron is 1.008665 amu.

Determine the binding energy of a F-19 nucleus.The F-19 nucleus has a mass of 18.99840325 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

The following reaction represents what nuclear process? 23592\begin{array} { c } 235 \\92\end{array}23592​ U + 10\begin{array} { l } 1 \\0\end{array}10​ n ? 13956\begin{array} { c } 139 \\56\end{array}13956​ Ba + 94 36 Kr + 3 10\begin{array} { l } 1 \\0\end{array}10​ n

The age of an ancient tree trunk is estimated using radiocarbon dating.If the trunk has a C-14 decay rate that is 34% of what it is in living plants,how old is the trunk? The half-life of C-14 is 5730 years.

Determine the binding energy of an O-16 nucleus.The O-16 nucleus has a mass of 15.9905 amu.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

Determine the binding energy per nucleon of a Mg-24 nucleus.The Mg-24 nucleus has a mass of 24.30506.A proton has a mass of 1.00728 amu,a neutron has a mass of 1.008665 amu,and 1 amu is equivalent to 931 MeV of energy.

A geological sample is found to have a Pb-206/U-238 mass ratio of 0.337/1.00.Assuming there was no Pb-206 present when the sample was formed,how old is it? The half-life of U-238 is 4.5 × 10⁹ years.

Fluorine-18 undergoes positron emission with a half-life of 1.10 × 10² minutes.If a patient is given a 248 mg dose for a PET scan,how long will it take for the amount of fluorine-18 to drop to 83 mg? (Assume that none of the fluorine is excreted from the body.)

Complete the following equation of transmutation. 14 7 N + 4 2 He ? $\begin{array} { c } 17 \\8\end{array}$ O + ________

The following reaction represents what nuclear process? $\begin{array} { l } 2 \\1\end{array}$ H + $\begin{array} { l } 2 \\1\end{array}$ H ? $\begin{array} { l } 3 \\2\end{array}$ He + $\begin{array} { l } 1 \\0\end{array}$ n

Complete the following equation of nuclear fusion. $\begin{array} { l } 2 \\1\end{array}$ H + $\begin{array} { l } 3 \\1\end{array}$ H ? 4 2 He + ________

The following reaction represents what nuclear process? $\begin{array} { c } 235 \\92\end{array}$ U + $\begin{array} { l } 1 \\0\end{array}$ n ? $\begin{array} { c } 139 \\56\end{array}$ Ba + 94 36 Kr + 3 $\begin{array} { l } 1 \\0\end{array}$ n