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Representation of the core of a molecule, ion or formula unit by showing atomic symbols and only outer shell electrons.

Latest Articles

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    In this paper I describe (theoretically) the method(s) of automated protein discovery and synthesis.

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    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...

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    If you happen to break a rotten egg, then you know the smell of hydrogen sulfide, because the stench of the spoiled egg depends on of its presence in rotting protein substances.

  • 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.



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Features of the Scanning Tunneling Microscope

The scanning tunneling microscope (STM) invented by Heinrich Rohrer and Gerd Binnig in the 1980s still manages to do a great job today and competes with more advanced microscope types.

The scanning tunneling microscope is used for studying the surface atoms that are found on various materials. The device is based on a complex process of "tunneling" electrons between the material and the tip of a probe.

Hess' Law of Heat Summation

The enthalpy change for a reaction is the same whether it occurs in one step or a series of steps.

Catalyst

A substance that speeds up a chemical reaction without being consumed itself in the reaction.
A substance that alters (usually increases) the rate at which a reaction occurs.

Ether

Compound in which an oxygen atom is bonded to two alkyl or two aryl groups, or one alkyl and one aryl group.

Noble Gases (Rare Gases)

Elements of the periodic Group 0, also called rare gases, formerly called inert gases, He,Ne,Ar, Kr, Xe, Rn.

Distillate

The material in a distillation apparatus that is collected in the receiver.

 

Radioactivity

The spontaneous disintegration of atomic nuclei.

Percent Purity

The percent of a specified compound or element in an impure sample.

Homogeneous Mixture

A mixture which has uniform composition and properties throughout.

Structural Isomers

Compounds that contain the same number of the same kinds of atoms in different geometric arrangements.