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The mass of one formula unit of a substance in atomic mass units.

 

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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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Substance

Any kind of matter all specimens of which have the same chemical composition and physical properties.

 

Hydration

Reaction of a substance with water.

Nonbonding Orbital

A molecular orbital derived only from an atomic orbital of one atom, lends neither stability nor instability to a molecule or ion when populated with electrons.

Ionization Energy

The minimum amount of energy required to remove the most loosely held electron of an isolated gaseous atom or ion.

Equivalence Point

The point at which chemically equivalent amounts of reactants have reacted.

Electrophoresis

A technique for separation of ions by rate and direction of migration in an electric field.

Enthalpy

The heat content of a specific amount of substance, defined as E= PV.

Do you know: some mosquitoes bite people because of their clothes

If you have ever been bitten by a mosquito, someone nearby surely gave you an explanation of why the nasty insect decided to spoil your day. Maybe they told you that you smelt good, or you had a certain type of blood or that in that shirt you looked like a potential victim.

Absolute Entropy (of a substance)

The increase in the entropy of a substance as it goes from a perfectly ordered crystalline form at 0 °K (where its entropy is zero) to the temperature in question.

Entropy is a measure of the “dilution” of thermal energy.

Binary Compound

A compound consisting of two elements, may be ionic or covalent.