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Any of a group of dyes having a molecular structure related to that of xanthene in which the aromatic (C6H4) groups are the chromophore.

 

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The most expensive metal in the world

Do you think the most expensive metal is gold? No! On earth there are more valuable metals. But we need to divide the value of metals that occur in nature, and metals - isotopes, which are obtained in special laboratories. Let’s look at natural metals first.

Saturated Hydrocarbons

Hydrocarbons that contain only single bonds. They are also called alkanes or paraffin hydrocarbons.

Zinc

Discovered: known in India and China before 1500 and to the Greeks and Romans before 20 BC as the copper-zinc alloy brass
Origin: The name is derived from the German ‘Zink’.
Atomic no: 30
Mass No: 65
Description: A grey metal with a blue tinge. World production exceeds 7 million tons a year, and it is used to galvanise iron to prevent it rusting. It is also employed in alloys and batteries, and as zinc oxide to stabilise rubber and plastics. Zinc is essential for all living things, and is important for growth and development. The average human body contains about 2.5 grams and takes in about 15 milligrams per day. Some foods have above average levels of zinc, including herring, beef, lamb, sunflower seeds and cheese.

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Chemindustry.com - Includes chemicals, chemical companies, engineering, and process equipment. Search tool for products, services, and information.
Chemicals HeadQuarters - Directory of industrial chemicals and chemical products including induced and forced air coolers, halogenated compounds, distilling equipment, and foundry resins.
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Chemical Week - Daily news and product updates for professionals in the chemical industry.
American Chemistry Council News and Media - Provides chemistry business and industry news, updated issue briefs, fact sheets, press releases, media contacts and other resources.
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Chemistry & Environmental Dictionary - Contains definitions for many chemistry, environmental and other related technical terms and acronyms.
EDF Chemical Scoreboard - Toxic Release Inventory data for the US. Sources and amounts of toxic chemicals released to air and water. Also has information on health effects and other topics.
Chemistry Articles - Collection of chemistry and chemical related articles.

 

Thermodynamics

The study of the energy transfers accompanying physical and chemical processes.

Le Chatelier's Principle

States that a system at equilibrium, or striving to attain equilibrium, responds in such a way as to counteract any stress placed upon it.
If a stress (change of conditions) is applied to a system at equilibrium, the system shifts in the direction that reduces stress.

Nuclear Fission

The process in which a heavy nucleus splits into nuclei of intermediate masses and one or more protons are emitted.

Use of diamonds

Diamond is a crystalline modification of pure carbon formed in the deep interior of the Earth, in the upper mantle at depths of more than 80-100 kilometers, at exceptionally high pressure and temperature. It is the most precious stone, the hardest and most wear-resistant mineral, the most brilliant and timeless gem.

Enantiomer

One of the two mirror-image forms of an optically active molecule.

Ionization Constant

Equilibrium constant for the ionization of a weak electrolyte.