Logarithmic scale is the one in which values of 1, 2, 3, 4, 5, in fact represents values of 1, 10, 100, 1 000, 10 000. Logarithmic scales are often used to simplify graphs and tables, where otherwise changes of data at the lower end of the scale would be difficult to distinguish (e.g. a graph axis which would normally have values from 1 - 1 000 000 is shown by values of 1 - 7). An example of a logarithmic scale is the pH scale.
Metre (m) is the SI base unit of length.
The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 s.
This definition, adopted by the General Conference on Weights and Measure in October 1983, replaced the 1967 definition based on the krypton lamp.
Minerals are compounds in which metals can be found in nature. Metals in nature can appear as:
| autochthonous | Au, Cu, Pt, Ag, Pd, Hg, Ir |
| oxides | Fe, Al, Sn, Cr, Mn, W, Cu |
| sulphides | Cu, Pb, Zn, Ni, Ag, Co, Sb, Hg, Mo, Cd, Bi |
| carbonates | Fe, Zn, Cu, Mg, Mn, Pb |
| silicates | Ni, Cu, Zn, Mn |
| chlorides | Ag, Cu, Mg, Na, K |
| sulphates | Ca, Ba, Sr, Cu |
X-ray spectrum is a set of characteristic X-ray frequencies or wavelengths produced by a substance used as a target in an X-ray tube. Each element has a characteristic X-ray spectrum, and there is a strong correlation between atomic number and the frequencies of certain lines in the X-ray spectrum.
Mohs’ scale of mineral hardness characterises the scratch resistance of various minerals through the ability of a harder material to scratch a softer. It was created by the German mineralogist Friedrich Mohs (1773-1839). Mohs based the scale on the ten readily available minerals.
| Hardness | Mineral |
|---|---|
| 1 | talc (Mg3Si4O10(OH)2) |
| 2 | gypsum (CaSO4·2H2O) |
| 3 | calcite (CaCO3) |
| 4 | fluorite (CaF2) |
| 5 | apatite (Ca5(PO4)3(OH-,Cl-,F-)) |
| 6 | orthoclase feldspar (KAlSi3O8) |
| 7 | quartz (SiO2) |
| 8 | topaz (Al2SiO4(OH-,F-)2) |
| 9 | corundum (Al2O2) |
| 10 | diamond (C) |
Mole (mol) is the SI base unit of amount of substance.
The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kg of carbon 12.
When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles. In this definition, it is understood that the carbon 12 atoms are unbound, at rest and in their ground state.
Nerve poison (nerve gas, agents) have had an entirely dominant role since the Second World War. Nerve poisons acquired their name because they affect the transmission of nerve impulses in the nervous system. All nerve poisons belong chemically to the group of organo-phosphorus compounds. They are stable and easily dispersed, highly toxic and have rapid effects both when absorbed through the skin and via respiration. Nerve poisons can be manufactured by means of fairly simple chemical techniques. The raw materials are inexpensive and generally readily available.
The most important nerve agents included in modern chemical weapons arsenals are:
| Tabun | (o-ethyl dimethylamidophosphorylcyanide) |
| Sarin | (isopropyl methylphosphonofluoridate) |
| Soman | (pinacolyl methylphosphonofluoridate) |
| GF | (cyclohexyl methylphosphonofluoridate) |
| VX | (o-ethyl S-diisopropylaminomethyl methylphosphonothiolate) |
Nerve poisons are colorless, odorless, tasteless liquids of low volatility. Antidotes are atropine sulfate and pralidoxime iodide.
Generalic, Eni. "/tab." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
Glossary
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