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

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  • 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 most famous type of garnet stone is pyrope (flaming). This is the "oldest of garnets", with a dense red color, similar to the grain of an edible garnet. Pyrope has a variety called rhodolite - a stone of dense pink or pink-purple color, which sometimes has the alexandrite effect and is used in...

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

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Physical Change

A change in which a substance changes from one physical state to another but no substances with different composition are formed. Example Gas to Liquid - Solid.

 

Nonelectrolyte

A substance whose aqueous solutions do not conduct electricity.

Periodicity

Regular periodic variations of properties of elements with atomic number (and position in the periodic table).

Flash Point

The temperature at which a liquid will yield enough flamable vapour to ignite. There are various recognized industrial testing methods, therefore the method used must be stated.

Halogens

Group VIIA elements: F, Cl, Br, I

Ideal Gas

A hypothetical gas that obeys exactly all postulates of the kinetic-molecular theory.

 

Homogeneous Equilibria

Equilibria involving only one species in a single phase. For example, all gases, all liquids or all solids.

Actinides

Elements 89 to 103 (between lawrencium and actinium) on the periodic table. Only the first four have been found in nature in appreciable amounts. The remainder have been produced synthetically.

Critical Pressure

The pressure required to liquefy a gas (vapor) at its critical temperature.

Atomic Radius

Radius of an atom.