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The amount of heat absorbed in the formation of one mole of a substance in a specified state from its elements in their standard states.

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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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    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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    One of the most interesting and obvious chemical experiments is the experiment on the interaction of copper sulfate and calcium carbonate. The latter is contained in the shell of a simple egg, but copper sulphate should be searched in a chemical reagent store. This experience is simple, but...

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Crystal Lattice Energy

Amount of energy that holds a crystal together, the energy change when a mole of solid is formed from its constituent molecules or ions (for ionic compounds) in their gaseous state.

Wild patina, is it so bad?

Usually this kind of patina appears on monuments. The most striking example is the Statue of Liberty in New York.

Anion

A negative ion, an atom or goup of atoms that has gained one or more electrons.

 

Ionization Energy

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

Coefficient of expansion

The ratio of the change in length or volumen of a body to the original lengthor volume for a unit change in temperature.

Salinometer

An instrument for measuring the amount of salt in a solution. Also,"salimeter, salometer."

Half-Cell

Compartment in which the oxidation or reduction half-reaction occurs in a voltaic cell.

Amphiprotism

Ability of a substance to exhibit amphiprotism by accepting donated protons.

Paramagnetism

Attraction toward a magnetic field, stronger than diamagnetism, but still weak compared to ferromagnetism.

Geiger counter

A gas filled tube which discharges electriaclly when ionizing radiation passes through it.