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Covalent bond resulting from the sharing of four electrons (two pairs) between two atoms.

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    Chemistry can teach us about the composition of celestial bodies and determine their age.

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

  • What are Compound Microscopes?

    Most of the microscopes used today are compound. A compound microscope features two or more lenses. A hollow cylinder called the tube connects the two lenses. The top lens, the one people look through, is called the eyepiece. The bottom lens is known as the objective lens. Below the two lenses is...

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    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...

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Daughter Nuclide

Nuclide that is produced in a nuclear decay.


Antibonding Orbital

A molecular orbital higher in energy than any of the atomic orbitals from which it is derived, lends instability to a molecule or ion when populated with electrons, denoted with a star (*) superscript or symbol.

Dumas Method

A method used to determine the molecular weights of volatile liquids.

yttrium metal

Any of a subgroup of rare-earth elements, of which the cerium and terbium metals comprise the other two subgroups.

Ternary Acid

A ternary compound containing H, O, and another element, often a nonmetal.

Percent Composition

The mass percent of each element in a compound.

Gas of rotten eggs

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.

Open Sextet

Refers to species that have only six electrons in the highest energy level of the central element (many Lewis acids).

Water Equivalent

The amount of water that would absorb the same amount of heat as the calorimeter per degree temperature increase.

Differential Thermal Analysis (DTA)

A technique for observing the temperature, direction, and magnitude of thermally induced transitions in a material by heating/cooling a sample and comparing its temperature with that of an inert reference material under similar conditions.