1 | Page
ENVS 1126 Exam 3 Questions and Correct
Answers
The concentration of U-235 needed to generate nuclear power is
approximately (1)___, but the concentration of U-235 needed to
generate nuclear weapons is approximately (2)___. Ans: (1) 4%, (2)
85%
The atomic number of oxygen is 8; this means: Ans: Oxygen has 8
protons in its nucleus
Nuclear bombs rely upon Ans: a domino effect that causes the
nuclear fission of uranium-235 in less than a second.
(1) What is really old-fashioned about nuclear power? (2) What is
really cutting-edge and innovative about nuclear power? (3) What
is really scary about nuclear power? Ans: (1) it's just heating water
to rotate a turbine. (2) It can provide power for extremely long
© 2025 All rights reserved
, 2 | Page
periods of time. (3) There is a possibility of a meltdown that harms
humans and the environment.
Answer the 3 following questions regarding isotopes: (1) Does
changing the number of neutrons change the number of protons?
(2) Does changing the number of neutrons change the atomic
number? (3) Does changing the number of neutrons change the
atomic mass? Ans: NO, NO, YES
Overtime the popularity of nuclear power has decreased. Which of
the following is not a reason for a decrease in the utilization of
nuclear energy? Ans: Low Energy Efficiency
A scientist is designing a prototype for a nuclear reactor that takes
two atomic nuclei and fuses them to create a heavier nucleus,
releasing a large amount of energy. Which of the following is an
example of this type of nuclear power? Ans: the sun
Carbon-12 and carbon-14 are isotopes of carbon. These isotopes
differ in the number of Ans: neurons
© 2025 All rights reserved
, 3 | Page
Isotopes have: Ans: The same atomic number but different atomic
mass
What is the difference between carbon-12, carbon-13, and carbon-
14? Ans: Carbon-12 has 6 protons and 6 neutrons; carbon-13 has 6
protons and 7 neutrons; carbon-14 has 6 protons and 8 neutrons
Which statement is not true about nuclear fission? Ans: The
energy from fission cannot be harvested by humans at the
moment
From the events discussed in class, the most recent nuclear
disaster took place in: Ans: Fukushima, Japan
This is not true about a nuclear power plant Ans: Produces acid
pollutants or particulates
What is nuclear fission? Ans: The splitting of an unstable atom
into 2 or more stable atoms, often resulting in the release of free
neutrons.
© 2025 All rights reserved
ENVS 1126 Exam 3 Questions and Correct
Answers
The concentration of U-235 needed to generate nuclear power is
approximately (1)___, but the concentration of U-235 needed to
generate nuclear weapons is approximately (2)___. Ans: (1) 4%, (2)
85%
The atomic number of oxygen is 8; this means: Ans: Oxygen has 8
protons in its nucleus
Nuclear bombs rely upon Ans: a domino effect that causes the
nuclear fission of uranium-235 in less than a second.
(1) What is really old-fashioned about nuclear power? (2) What is
really cutting-edge and innovative about nuclear power? (3) What
is really scary about nuclear power? Ans: (1) it's just heating water
to rotate a turbine. (2) It can provide power for extremely long
© 2025 All rights reserved
, 2 | Page
periods of time. (3) There is a possibility of a meltdown that harms
humans and the environment.
Answer the 3 following questions regarding isotopes: (1) Does
changing the number of neutrons change the number of protons?
(2) Does changing the number of neutrons change the atomic
number? (3) Does changing the number of neutrons change the
atomic mass? Ans: NO, NO, YES
Overtime the popularity of nuclear power has decreased. Which of
the following is not a reason for a decrease in the utilization of
nuclear energy? Ans: Low Energy Efficiency
A scientist is designing a prototype for a nuclear reactor that takes
two atomic nuclei and fuses them to create a heavier nucleus,
releasing a large amount of energy. Which of the following is an
example of this type of nuclear power? Ans: the sun
Carbon-12 and carbon-14 are isotopes of carbon. These isotopes
differ in the number of Ans: neurons
© 2025 All rights reserved
, 3 | Page
Isotopes have: Ans: The same atomic number but different atomic
mass
What is the difference between carbon-12, carbon-13, and carbon-
14? Ans: Carbon-12 has 6 protons and 6 neutrons; carbon-13 has 6
protons and 7 neutrons; carbon-14 has 6 protons and 8 neutrons
Which statement is not true about nuclear fission? Ans: The
energy from fission cannot be harvested by humans at the
moment
From the events discussed in class, the most recent nuclear
disaster took place in: Ans: Fukushima, Japan
This is not true about a nuclear power plant Ans: Produces acid
pollutants or particulates
What is nuclear fission? Ans: The splitting of an unstable atom
into 2 or more stable atoms, often resulting in the release of free
neutrons.
© 2025 All rights reserved
