Closed glass tube containing a gas under low pressure, with electrodes near the ends and a luminescent screen at the end near the positive electrode, produces cathode rays when high voltage is applied.
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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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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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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...
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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.
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Chemistry of the sky
Chemistry can teach us about the composition of celestial bodies and determine their age.
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Primary Standard
A substance of a known high degree of purity that undergoes one invariable reaction with the other reactant of interest.
Condensed States
The solid and liquid states.
Free Radical
A highly reactive chemical species carrying no charge and having a single unpaired electron in an orbital.
Enzyme
A protein that acts as a catalyst in biological systems.
Wild patina, is it so bad?
Usually this kind of patina appears on monuments. The most striking example is the Statue of Liberty in New York.
Aufbau ('building up') Principle
Describes the order in which electrons fill orbitals in atoms.
Iron
Discovered : known to ancient civilisations.
Origin : The name comes from the Anglo-Saxon ‘iren’, and the symbol from the Latin ‘ferrum’, meaning iron.
Description :Iron is an enigma - it rusts easily and yet is the most important of all metals, world production exceeds 700 million tons a year. Small amounts of carbon are added to iron to produce steel and when chromium.
is added to this, the result is non-corroding stainless steel (small amounts of nickel may also be added). Iron is also an essential element for all forms of life. The average human contains about 4 grams, much of which circulates as haemoglobin in the blood, the job of which is to carry oxygen from our lungs to where it is needed. If the diet does not contain 10 milligrams a day, anaemia will eventually develop. Foods such as liver, kidney, molasses, brewer’s yeast, cocoa and liquorice contain a lot of iron.
Atomic No:26 Mass No:56
Alkali Metals
Metals of Group IA (Na, K, Rb).
Chemistry is a familiar school subject
Everyone liked to observe the reaction of reagents. But few know interesting facts about chemistry, which we will discuss in this article.
Spectral Line
Any of a number of lines corresponding to definite wavelengths of an atomic emission or absorption spectrum, represents the energy difference between two energy levels.
