M.Elizabeth Chemistry 2011-2012
Matter: Properties and Changes, Atomic Structure, Nuclear Chemistry
Resources
- GUHS Atomic Structure and Nuclear Reactions SG word
- 2011-2012 Unit 2 Interactive notebook word
- Textbook Chapter 3 ppt
- Matter ppt
- Matter and Elements ppt
- Chapter 4 ppt
- Atoms Discovery ppt
- Atoms Structure ppt
- Writing formula ppt
- Nuclear Chemistry ppt
- Nuclear Reactions ppt
- Chapter 25 ppt
Movies
States of Matter movie
Discovery of the Atom movie
Conservation of Mass movie
Conservation of Mass Notes and Problems word 1 word 2
Cathode Ray Tube movie
Cloud-Chamber movie
Detecting Radiation movie
Fission Reactions movie
Positrons movie
Nuclear Plants Fission movie
Radiocarbon Dating movie
Practice
Atomic Number Practice pdf
Atomic Structure Practice pdf
Mass Number Practice pdf
Isotopes Practice pdf
Average Atomic Mass pdf
Nuclear Chemistry Handouts
Tutorial Nuclear Reactions
Overview link with tutorial
Self test quiz
Science Geeks nuclear chemistry
Nuclear Chemistry Notes word
Nuclear ppt
Nuclear Chemistry Navy
Backgrounder pdf
Georgia notes pdf 1 pdf 2 Georgia video 1 2
Balancing Practice word
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Online Resources (Web Sites)
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TEXTBOOK RESOURCES
Matter: Properties and Change; Atomic Structure (August 27 - September 18)
Really start to get into Chemistry, especially some of the basics of GREATEST table ever
The Periodic Table (CST Periodic Table pdf)
Chapter 3 - Matter: Properties and Change
contains the following topics:
Properties of Matter
Changes in Matter
Mixtures of Matter
Elements vs. Compounds
What is the difference between a physical change and a chemical change?
Do YOU know it when you see it?
Chapter 4 - The Structure of the Atom - contains the following topics:
Early Theories of Matter
Subatomic Particles and the Nuclear Atom
How Atoms Differ
Unstable Nuclei and Radioactive Decay
Chapter 25 - Nuclear Chemistry - contains the following topics:
Nuclear Radiation
Radioactive Decay
Transmutation
Fission and Fusion of Atomic Nuclei
Applications and Effects of Nuclear Reactions
Nuclear processes are those in which an atomic nucleus changes, including radioactive decay of naturally occurring and human-
made isotopes, nuclear fission, and nuclear fusion. Protons and neutrons in the nucleus are held together by strong nuclear
forces that overcome the electromagnetic repulsion between the protons. The strong nuclear force acts between protons,
between neutrons, and between protons and neutrons but has a limited range comparable to the size of an atomic nucleus. The
nuclear force is able to overcome the mutual electrostatic repulsion of the protons only when the protons and neutrons are
near each other as they are in the nucleus of an atom. Energy release per gram of material is much larger in nuclear fusion or
fission reactions than in chemical reactions. The change in mass (calculated by E = mc2 ) is small but significant in nuclear
reactions.
Two major types of nuclear reactions are fusion and fission. In fusion reactions two nuclei come together and merge to form a
heavier nucleus. In fission a heavy nucleus splits apart to form two (or more) lighter nuclei.
The three most common forms of radioactive decay are alpha, beta, and gamma. Decay occurs when radioactive isotopes
transform to more stable isotopes, emitting particles from the nucleus. These particles are helium-4 nuclei (alpha radiation),
electrons or positrons (beta radiation), or high-energy electromagnetic rays (gamma radiation). Alpha and beta decay are
ionizing radiations with the potential to damage surrounding materials. After alpha and beta decay, the resulting nuclei often
emit high-energy photons called gamma rays. This process does not change the number of nucleons in the nucleus of the isotope
but brings about a lower energy state in the nucleus.
Alpha, beta, and gamma radiation produce different amounts and kinds of damage in matter and have different
penetrations.
Alpha, beta, and gamma rays are ionizing radiations, meaning that those rays produce tracks of ions of atoms and molecules
when they interact with materials.
- Alpha particles have the shortest ranges, and matter such as paper that is only a few millimeters thick will stop them.
They will not penetrate a thick sheet of paper but will deposit all their energy along a relatively short path, resulting in
a high degree of ionization along that path.
- Beta particles have longer ranges, typically penetrating matter up to several centimeters thick, but can be blocked by
aluminium. Those particles are electrons or positrons (the antimatter electron), have one unit of either negative or
positive electric charge, and are approximately 1/2000 of the mass of a proton. These high-energy electrons have
longer ranges than alpha particles and deposit their energy along longer paths, spreading the ionization over a greater
distance in the material.
- Gamma rays can penetrate matter such as lead up to several meters thick. Gamma rays are high-energy photons that
have no electric charge and no rest mass (the structural energy of the particle). They will travel unimpeded through
materials until they strike an electron or the nucleus of an atom. The gamma ray’s energy will then be either completely
or partially absorbed, and neighboring atoms will be ionized. Therefore, these three types of radiation interact with
matter by losing energy and ionizing surrounding atoms.
Alpha radiation is dangerous if ingested or inhaled. For example, radon-222, a noble gas element, is a naturally occurring
hazard in some regions. Living organisms or sensitive materials can be protected from ionizing radiation by shielding them and
increasing their distance from radiation sources.
Each form of radiation has different abilities to penetrate matter and cause damage. The order of penetrating ability, from
greatest to least, is gamma > beta > alpha, and this order is the basis for assessing proper shielding of radiation sources for
safety. BUT don't think that ingestion of alpha radioactive particles will leave you alive, because it maynot.





