Wagner tube or drop catcher impedes the movement of distillate drops from the distillation flask to the condensing chamber.
Plastic wash bottle is a squeeze bottle made of low density polyethylene (LDPE) whose contents can be forced out through a narrow hole at the top by squeezing the bottle.
Glass wash bottle is a bottle fitted with two glass tubes pass through the cap, so that on blowing into one of the tubes a stream of water issuing from the other may be directed upon anything to be washed or rinsed, as a precipitate upon a filter.
Water (H2O) (dihydrogen oxide) is a binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 °C and boils above 100 °C. Water is a chemical compound which is essential for living organisms and it is widely used as a solvent.
Wire mesh (wire gauze) is used for uniform distribution of flame heat in base of a heated body. It is made of a iron wire strands with or without ceramic interior cores.
Hardness is defined as the concentrations of calcium and magnesium ions expressed in terms of calcium carbonate. These minerals in water can cause some everyday problems. They react with soap and produce a deposit called soap curd that remains on the skin and clothes and, because it is insoluble and sticky, cannot be removed by rinsing.
Hard water may also shorten the life of plumbing and water heaters. When water containing calcium carbonate is heated, a hard scale is formed that can plug pipes and coat heating elements. Scale is also a poor heat conductor. With increased deposits on the unit, heat is not transmitted to the water fast enough and overheating of the metal causes failure. Build-up of deposits will also reduce the efficiency of the heating unit, increasing the cost of fuel.
There are two types of water hardness, temporary and permanent.
Temporary Hardness is due to the bicarbonate ion, HCO3-, being present in the water. This type of hardness can be removed by boiling the water to expel the CO2, as indicated by the following equation:
Permanent hardness is due to calcium and magnesium nitrates, sulphates, and chlorides etc. This type of hardness cannot be eliminated by boiling.
Water supply classification | |
---|---|
Hardness | Concentration of Calcium carbonate (mg/L) |
Soft Water | 0 to 75 |
Medium Hard Water | 75 to 150 |
Hard Water | 150 to 300 |
Very Hard Water | over 300 |
The regular array of atoms in a crystal is a three-dimensional diffraction grating for short-wavelength waves such as X-rays. The atoms are arranged in planes with interplanar spacing d. Diffraction maxima occur in the incident direction of the wave, measured from the surface of a plane of atoms, and the wavelength λ of the radiation satisfy Braggs’s law:
X-ray tube is a cathode ray tube that focuses energetic streams of electrons on a metal target, causing the metal to emit X-rays. The basic principle of the X-ray tube has not changed significantly since Roentgen's 1895 discovery. Current applied to a metal cathode (about 50 000 V) produces free electrons. The X-rays are produced when the rapidly moving electrons are suddenly stopped as they strike the metal target of the tube.
X-rays are electromagnetic radiation of shorter wavelength than ultraviolet radiation (10-11 m to 10-9 m or 0.01 nm to 1 nm) produced by bombardment of atoms by high-quantum-energy particles. X-rays can pass through many forms of matter and they are therefore used medically and industrially to examine the internal structure.
Zeeman effect is the splitting of the lines in a spectrum when the source of the spectrum is exposed to a magnetic field. The effect was discovered in 1896 by the Dutch physicist Pieter Zeeman (1865-1943) as a broadening of the yellow D-lines of sodium in a flame held between strong magnetic poles.
The Zeeman effect has helped physicists determine the energy levels in atoms. In astronomy, the Zeeman effect is used in measuring the magnetic field of the Sun and of other stars.
Zeolite is a natural or synthetic hydrated aluminosilicate with an open three-dimensional crystal structure, in which water molecules are held in cavites in the latice. The water can be driven off by heating and the zeolite can then absorb other molecules of suitable size. Zeolites are used for separating mixtures by selective absorption.
Generalic, Eni. "Curtain rod width." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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