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A number that indicates how smoothly a gasoline burns.

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  • Creating Malachite egg

    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...

  • Ozone

    We breathe 24 hours a day, 7 days a week, consuming about 25 kg of air every day. It turns out that we practically predetermine our health by the air we breathe.

  • Varieties of garnet minerals

    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...

  • 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.

  • 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.

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Equation of State

An equation that describes the behavior of matter in a given state, the van der Waals equation describes the behavior of the gaseous state.


Process that occurs in electrolytic cells.

Evaporation Rate

The rate at which a particular substance will vapourize (evaporate) when compared to the rate of a known substance such as ethyl ether. This term is especially useful for health and fire-hazard considerations.

Coordination Number

In describing crystals, the number of nearest neighbours of an atom or ion. The number of donor atoms coordinated to a metal.

Use of diamonds

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 brilliant and timeless gem.

Nuclear Reaction

Involves a change in the composition of a nucleus and can evolve or absorb an extraordinarily large amount of energy.

Activity of a component of ideal mixture

A dimensionless quantity whose magnitude is: equal to molar concentration in an ideal solution, equal to partial pressure in an ideal gas mixture, and defined as 1 for pure solids or liquids.

Donor Atom

A ligand atom whose electrons are shared with a Lewis acid.

Differential Scanning Calorimetry (DSC)

A technique for measuring the temperature, direction, and magnitude of thermal transitions in a sample material by heating/cooling and comparing the amount of energy required to maintain its rate of temperature increase or decrease with an inert reference material under similar conditions.


A physical state of matter which exists at extremely high temperatures in which all molecules are dissociated and most atoms are ionized.