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A sample of matter composed of two or more substances, each of which retains its identity and properties.

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  • Protein Design: Automated protein discovery and synthesis

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

  • 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...

  • 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.

  • Why do copper products change color, and what is the name of the process?

    Probably, every person wants to know, why over time the copper turns green and becomes bloomed. This is easy to explain: that film is called patina.

  • 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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D -Transition elements (metals)

B Group elements except IIB in the periodic table, sometimes called simply transition elements EX. Fe, Ni, Cu, Ti .
For further information see Metals.

Primary Voltaic Cells

Voltaic cells that cannot be recharged, no further chemical reaction is possible once the reactants are consumed.

Law of Partial Pressures (Dalton's Law)

The total pressure exerted by a mixture of gases is the sum of the partial pressures of the individual gases.

Ternary Compound

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

Crystal Field Theory

Theory of bonding in transition metal complexes in which ligands and metal ions are treated as point charges, a purely ionic model, ligand point charges represent the crystal (electrical) field perturbing the metal?s d orbitals containing nonbonding electrons.

xanthene dye

Any of a group of dyes having a molecular structure related to that of xanthene in which the aromatic (C6H4) groups are the chromophore.


Coordinate Covalent Bond

A covalent bond in which both shared electrons are donated by the same atom, a bond between a Lewis base and a Lewis acid.

Absolute Zero

The zero point on the absolute temperature scale, -273.15°C or 0 K, theoretically, the temperature at which molecular motion ceases. The concept of an absolute zero temperature was first deduced from experiments with gases. When a fixed volume of gas is cooled, its pressure decreases with its temperature. Absolute zero physically possesses quantum mechanical zero-point energy.


Discovered : by Henry Cavendish in 1766.
Isolated in London, UK.
Origin : The name is derived from the Greek ‘hydro genes’, meaning water forming.
Description :A colourless, odourless gas that burns and can form an explosive mixture with air. It is currently manufactured from methane gas, but is also produced by the electrolysis of water and aqueous salts. The gas is used to make such key materials as ammonia, cyclohexane and methanol, which are intermediates in the production of fertilisers, plastics and pharmaceuticals. Some see hydrogen gas as the clean fuel of the future - generated from water and returning to water when it is oxidised. Hydrogen-powered fuel cells are increasingly being seen as pollution-free sources of energy.

Radioactive Dating

Method of dating ancient objects by determining the ratio of amounts of mother and daughter nuclides present in an object and relating the ratio to the object?s age via half-life calculations.