CHEMISTRY GLOSSARY
metal → metal
Metals are materials in which the highest occupied energy band (conduction band) is only partially filled with electrons.
Their physical properties generally include:
- They are good conductors of heat and electricity. The electrical conductivity of metals generally decreases with temperature.
- They are malleable and ductile in their solid state.
- They show metallic lustre.
- They are opaque.
- They have high density.
- They are solids (except mercury)
- They have a crystal structure in which each atom is surrounded by eight to twelve near neighbours
Their chemical properties generally are:
- They have one to four valence electrons.
- They have low ionisation potentials; they readily lose electrons.
- They are good reducing agents.
- They have hydroxides which are bases or amphoteric.
- They are electropositive.
Metallic characteristics of the elements decrease and non-metallic characteristics increase with the increase of valence electrons. Also metallic characteristics increase with the number of electron shells. Therefore, there is no sharp dividing line between the metals and non-metals.
Of the 114 elements now known, only 17 show primarily non-metallic characteristics, 7 others are metalloids, and 89 may be classed as metals.
oxidation number → oksidacijski broj
Atoms can give one or more electrons for bond forming. The valence of any atom, which comes from stechiometrical relation of interbonded atoms, is called an oxidation number or an oxidation degree. Oxidation number of atoms in elementary state is zero. An atom of greater electronegativity has a negative, and an atom of lesser electronegativity has a positive oxidation number.
Paschen series → Paschenova serija
Paschen series are the series of lines in the spectrum of the hydrogen atom which corresponds to transitions between the state with principal quantum number n = 3 and successive higher states.
phosphorescence → fosforescencija
Phosphorescence is emission of light from a substance exposed to radiation and persisting as an afterglow after the exciting energy has been removed. Unlike fluorescence, in which the absorbed energy is spontaneously emitted about 10-8 second after excitation, phosphorescence requires additional excitation to produce radiation and may last from about mili second to days or years, depending on the circumstances.
plasma → plazma
Plasma is a highly ionised gas in which the charge of the electrons is balanced by the charge of the positive ions, so that the system as a whole is electrically neutral. Plasmas are created by exposing gases at low pressure to an electric or electromagnetic field. In semiconductor processing, plasmas are used for etching and thin film deposition (the excited state of the gas makes it very reactive). In everyday life plasmas are used to give light in fluorescent light bulbs, neon lamps, and blue insect traps.
potential energy → potencijalna energija
Potential energy (Ep) is the energy stored in a body or system as a consequence of its position, shape, or state (this includes gravitation energy, electrical energy, nuclear energy, and chemical energy). Gravitational potential energy is the energy associated with the state of separation between bodies that attracts each other via gravitational force. Elastic potential energy is the energy associated with the state of compression or extension of an elastic object. Thermal energy is associated with the random motions of atoms and molecules in a body.
sacrificial protection → zaštita žrtvovanom elektrodom
Sacrificial protection is the protection of iron or steel against corrosion by using a more reactive metal. Pieces of zinc or magnesium alloy are attached to pump bodies and pipes. The protected metal becomes the cathode and does not corrode. The anode corrodes, thereby providing the desired sacrificial protection. These items are known as sacrificial anodes and "attract" the corrosion to them rather than the iron/steel. The sacrificial anodes must be replaced periodically as they corrode.
The iron pipe will be connected to a more reactive metal such as magnesium through cooper wires, the magnesium will donate its electrons to the iron preventing it from rusting. Iron which is oxidises will immediately be reduced back to iron.
saturated fat → zasićena mast
Saturated fats are fats in foods that are solid at room temperature. They come chiefly from animal sources (beef, whole-milk dairy products, dark meat poultry) but also from tropical vegetable oils (coconut, palm).
saturated solution → zasićena otopina
Saturated solution is a solution that holds the maximum possible amount of dissolved material. When saturated, the rate of dissolving solid and that of recrystallisation solid are the same, and a condition of equilibrium is reached. The amount of material in solution varies with temperature; cold solutions can hold less dissolved solid material than hot solutions. Gases are more soluble in cold liquids than in hot liquids.
Citing this page:
Generalic, Eni. "Plinovito agregatno stanje." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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