1. When controlled, nuclear energy has many practical uses…
CHAPTER 10
Nuclear Chemistry
When controlled, nuclear energy has many practical uses…
This submarine is powered by a fission reaction that releases large amounts of energy

2. 10.1 Radioactivity Key Concepts What happens during nuclear decay?
What are three types of nuclear radiation?
How does nuclear radiation affect atoms?
What devices can detect nuclear radiation?

3. The image was caused by __________ that had not been observed before.
When Henri ____________ placed uranium salts on a photographic plate and then developed the plate, he found a __________ image.
The image was caused by __________ that had not been observed before.
He shared the 1903 Nobel Prize for Physics with Marie and Pierre ___________.
Becquerel
foggy
rays
Curie

4. Nuclear Decay
Radioactivity is the process in which an ______________ atomic nucleus emits charged particles and energy.
Any atom containing an unstable nucleus is called a radioactive isotope, or _________________ for short.
During nuclear decay, atoms of one element can change into atoms of a ______________ element altogether.
different
unstable
radioisotope

5. Types of Nuclear Radiation
Scientists can detect a radioactive substance by measuring the nuclear radiation it gives off.
Nuclear radiation is charged _______________ and _________________ that are emitted from the nuclei of radioisotopes.
What does the word emitted mean?
particles
energy
given off / released

6. Types of Nuclear Radiation

7. Types of Nuclear Radiation
Alpha Decay
An alpha particle is a ________________ charged particle made up of two protons and two neutrons—the same as a ____________ nucleus.
When a uranium-238 sample decays, it emits alpha particles.
An alpha particle has a 2+ charge
An alpha particle has a mass of 4 amu.
The symbol for an alpha particle, ______, shows its mass and charge.
positively
helium 4 2 He

8. Types of Nuclear Radiation
The nuclear equation for the alpha decay of uranium-238 is shown below.
The mass number on the left (238) ____________ the sum of the mass numbers on the right (____________).
The atomic number on the left (92) equals the sum of the atomic numbers on the right (___________).
The equation is ________________. =
equals
238 92
balanced

9. Types of Nuclear Radiation
A beta particle is an ______________ emitted by an unstable nucleus.
The symbol for a beta particle is _______.
During beta decay, a neutron decomposes into a proton and an electron. The proton stays trapped in the nucleus, while the electron is released.
A beta particle is assigned an atomic # of ______. A beta particle is assigned a mass number of ____.
electron -1 e -1

10. Types of Nuclear Radiation
The balanced equation for beta decay of thorium-234 is shown below. =

11. Types of Nuclear Radiation
Gamma Decay
A gamma ray is a penetrating ray of __________ emitted by an unstable nucleus.
Gamma radiation has ____ mass and ____charge.
Like X-rays and visible light, gamma rays are energy waves that travel through __________ at the speed of light.
energy no no
space

12. Types of Nuclear Radiation
Gamma radiation also involves balanced equations, but the energy of the nucleus __________________.
decreases
energy
emitted

13. Types of Nuclear Radiation
The penetrating power of nuclear radiation varies with the type.

14. Types of Nuclear Radiation
Balancing Nuclear Equations
Write a balanced nuclear equation for the alpha decay of polonium-210.
206 = Pb 82
Look up atomic #
on P.T.

15. Write a balanced nuclear equation for the beta decay of carbon-14.= N 7
Look up atomic #
on P.T.

16. Effects of Nuclear Radiation
Background radiation is nuclear radiation that occurs _______________ in the environment.
Radioisotopes in air, water, rocks, plants, and animals all contribute to background radiation.
Cosmic rays are streams of charged particles (mainly protons and alpha particles) from outer space.
Background radiation levels are generally ________ enough to be safe.
naturally
low

17. Effects of Nuclear Radiation
When nuclear radiation exceeds background levels, it can ____________ the cells and tissues of your body.
Nuclear radiation can ______________ atoms.
It may break the bonds in your _________, affecting cell functions.
damage
ionize
DNA

18. Effects of Nuclear Radiation
__________ gas is produced underground as the uranium in rocks and soil decays.
Radon
Insulation, modern windows, and modern building materials keep radon from escaping.
Radon gas dissolved in water is released through agitation.
Radon naturally diffuses up through the ground.
Radon enters through pinholes and cracks in the foundation.
Radon is produced by the nuclear decay of uranium found in rocks and soil.
Causes lung cancer

19. Detecting Nuclear Radiation
A ______________ counter uses a gas-filled tube to measure ionizing radiation.
When nuclear radiation enters the tube, it ionizes the atoms of the gas.
The ions produce an electric
______________, which can be
measured.
Many people who work with or
near radioactive materials wear
_______________ to monitor
their exposure to nuclear radiation.
Geiger
current
film badges

20. What happens when an atomic nucleus decays?
Assessment Questions
What happens when an atomic nucleus decays?
The atom loses an electron and gains energy.
Some of the protons in the nucleus are converted to neutrons.
A nucleus breaks into two parts of approximately equal mass.
An unstable nucleus emits charged particles and energy.

21. During alpha decay, the nucleus emits an alpha particle, or
Assessment Questions
During alpha decay, the nucleus emits an alpha particle, or
proton.
neutron.
deuterium nucleus.
helium nucleus.

22. Assessment Questions
Which isotope balances the nuclear equation for the alpha decay of thorium-232?

23. Nuclear radiation can damage cells in the body by
Assessment Questions
Nuclear radiation can damage cells in the body by
ionizing atoms in molecules in the cell.
making holes in the cell wall.
making isotopes in the cell radioactive.
causing water to vaporize and rupture the cell.

24. Assessment Questions
5. A Geiger counter measures radiation by detecting ions formed when charged particles pass through a tube filled with gas. True False