Jul 25 2014

RADIOACTIVITY

Radioactivity

Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability. Because the nucleus experiences the intense conflict between the two strongest forces in nature, it should not be surprising that there are many nuclear isotopes which are unstable and emit some kind of radiation. The most common types of radiation are called alpha, beta, and gamma radiation, but there are several other varieties of radioactive decay.

Radioactive decay rates are normally stated in terms of their half-lives, and the half-life of a given nuclear species is related to its radiation risk. The different types of radioactivity lead to different decay paths which transmute the nuclei into other chemical elements. Examining the amounts of the decay products makes possible radioactive dating.

Radiation from nuclear sources is distributed equally in all directions, obeying the inverse square law.

Natural radioactive decay series. Radioactive items you can buy. Some history.
Illustration of alpha, beta and gamma radiation
 

HyperPhysics***** Nuclear R Nave
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Mar 1 2014

chemistry Topic

 

 Measurement  Elements, Compounds, and Mixtures  Stoichiometry
Gases  Thermochemistry  Structure of the Atom
 An Introduction to Ionic Compounds The Covalent Bond  Main-Group Metals
 Redox Reactions The Chemistry of Nonmetals  Acids and Bases
 Transition-Metal Chemistry  The Structure of Solids Liquids
Solutions  Gas-Phase Reactions  Acid-Base Equilibria
 Solubility and Complex-Ion Equilibria Oxidation-Reduction Reactions  Electrochemistry
 Chemical Thermodynamics  Chemical Kinetics Nuclear Chemistry
Intermolecular Forces  Introduction to Organic Chemistry  Introduction to Materials Science
Organic Chemistry: Structure and
Nomenclature of Hydrocarbons		  Organic Chemistry: Functional Groups Organic Chemistry:
Reaction Mechanisms
 Introduction to Polymers  Introduction to Biochemistry

 Beginners might click here

Mar 1 2014

Solutions

Like Dissolves Like Hydrophilic and Hydrophobic Molecules
Soaps, Detergents, and Dry-Cleaning Agents Units of Concentration

Like Dissolves Like

By convention, we assume that one or more solutes dissolve in a solvent to form a mixture known as the solution. The photographs that accompany this section illustrate what happens when we add a pair of solutes to a pair of solvents.

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