Many representative elements attain at least a share of eight electrons in their valence shells when they form molecular or ionic compounds, there are some limitations.
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Features of the Scanning Tunneling Microscope
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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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...
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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.
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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.
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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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Isomorphous
Refers to crystals having the same atomic arrangement.
Conformations
Structures of a compound that differ by the extent of rotation about a single bond.
Specific Heat
The amount of heat required to raise the temperature of one gram of substance one degree Celsius.
Rate of Reaction
Change in the concentration of a reactant or product per unit time.
Nucleons
Particles comprising the nucleus, protons and neutrons.
Hydrogen
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.
Critical Mass
The minimum mass of a particular fissionable nuclide in a given volume required to sustain a nuclear chain reaction.
Salicylate
A salt or ester of salicylic acid.
Lanthanide Contraction
A decrease in the radii of the elements following the lanthanides compared to what would be expected if there were no f-transition metals.
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 elite jewelry.
