1. CONCURRENT ENROLLMENT CHEMISTRY
CHAPTER 10
CONCURRENT ENROLLMENT CHEMISTRY

2. RADIOACTIVE NUCLEI
Nuclei that undergo spontaneous changes and emit energy in the form of radiation
Henri Becquerel- 1896
Radioactive decay
Unstable nuclei emit radiation to attain more stable atomic configurations in a process called radioactive decay.

3. RADITATION Three types of radiation Alpha particles 42α or 42He 2+
Identical to helium nuceli

4. BETA PARITCLES Beta particles -10β or -10e-
Identical to an electron but is produced when a neutron becomes a proton by releasing an electron

5. GAMMA RAYS Gamma rays have no mass or charge. 00γ
Gamma rays are high-energy electromagnetic radiation.
Gamma rays almost always accompany alpha and beta radiation.
X rays are a form of high-energy electromagnetic radiation emitted from certain materials in an excited state.
The ability of radiation to pass through matter is called its penetrating power.
Gamma rays are highly penetrating because they have no charge and no mass
Learning check page 314

6. CONTINUED

7. Except for gamma radiation, radioactive decay involves transmutation, or the conversion of an element into another element.
Protons and neutrons are referred to as nucleons.
All nucleons remain in the dense nucleus because of the strong nuclear force.
The strong nuclear force acts on subatomic particles that are extremely close together and overcomes the electrostatic repulsion among protons.

8. CONTINUED
The area on the graph within which all stable nuclei are found is known as the band of stability
The band ends at Pb-208; all elements with atomic numbers greater than 83 are radioactive.

9. Positron and electron capture
Daughter nuclei
Learning check page 315
Positron
10e+
This is used in PET scans of the brain
Proton changes into a neutron
Electron capture
Learning checks on pages 315 and 316
Table 10-2 on page 313

11. Writing and Balancing Nuclear Equations

12. ISOTOPE HALF-LIFE
The time required for one-half the unstable nuclei in a sample to undergo radioactive decay
Learning checks 317 and 318
N is the remaining amount.
N0 is the initial amount.
n is the number of half-lives that have passed.
t is the elapsed time and T is the duration of the half-life.

13. CONTINUED Free radical Radiation sickness Table 10.3 page 319
An electron-deficient particle that is very reactive
Radiation sickness
Table 10.3 page 319

14. MEASUREMENTS Curie Becquerel Roentgen Rad
Unit of radiation measurement corresponding to 3.7 X 1010 nuclear disintegrations per second
Becquerel
Unit of radiation measurement corresponding to one nuclear disintegration per second
Roentgen
A biological unit of radiation measurement used with X rays and gamma rays; the quantity of radiation that generates 2.1 X 109 ion pairs per 1 cm3 of dry air or 1.8 X 1012 ion pairs per 1 g of tissue
Rad
A biological unit of radiation measurement corresponding to the transfer of 2.1 X 10-3 cal of energy to 1 kg of tissue

15. CONTINUED Gray Rem Geiger-Müller tube or counter
A biological unit of radiation measurement corresponding to the transfer of 1 J of energy to 1 kg of tissue
Rem
A biological unit of radiation measurement corresponding to the health effect produced by 1 roentgen of gamma or X-ray regardless of the type of radiation involved
Geiger-Müller tube or counter
A radiation-detection device operating on the principle that ions form when radiation passes through a tube filled with low-pressure gas

16. MEDICAL USES OR RADIOISOTOPES
Tracer
A radioisotope used medically because its progress through the body or localization in specific organs can be followed.
Tracers should have short half-lives
Daughter produced from decaying isotope should be nontoxic
Radioisotope should have a long enough half-life to be prepared and administered
Radiation given off by the isotope should be penetrating gamma rays, so they can be detected
Hot spot
Cold spot

17. CONTINUED
Radioisotopes administered internally for therapeutic use should ideally
Emit less penetrating alpha or beta radiation to restrict the extent of damage
Half-life should be long enough to allow sufficient time for the desired therapy
Decay products should be nontoxic and give off little or no radiation
Target tissue should concentrate the radioisotope to restrict the radiation damage
Table 10.6 page 324

18. NONMEDICAL USES Radioactive dating Nuclear fission Chain reaction
A process for determining the age of artifacts and rocks, based on the amount and half-life of radioisotopes contained in the object
Carbon-14 dating uses its half-life of 5600 years
Nuclear fission
A process in which large nuclei split into smaller, approximately equal-sized nuclei when bombarded by neutrons
Chain reaction
A nuclear reaction in which the products of one reaction cause a repeat of the reaction to take place. In the case of uranium fission, neutrons from fission reactions cause other fission reaction to occur

19. CONTINUED Branching chain reaction Critical reaction
A reaction in which the products of one reaction cause more than one more reaction to occur
Critical reaction
A constant-rate chain reaction
Supercritical reaction
A branching chain reaction
Critical mass
The minimum amount of fissionable material needed to sustain a critical chain reaction at a constant rate
Supercritical mass
The minimum amount of fissionable material that must be present to cause a branching chain reaction to occur

20. LAST PAGE Breeding reactions Thermonuclear reactions Nuclear fusion
A nuclear reaction in which isotopes that will not undergo spontaneous fission are changed into isotopes that will
Thermonuclear reactions
Nuclear fusion reactions that require a very high temperature to start them
Nuclear fusion
A process in which small nuclei combine or fuse to form larger nuclei