harmony
发表于 2025-3-28 17:44:50
Chromium Group: Elements of the Sixth Subgroup,s, however, compounds of chromium-VI are found in the electroplating and leather processing industry. Molybdenum and tungsten go into hard and high-melting alloys, but their nitrides and carbides are especially important for the electronics industry. Isotopes of seaborgium do not occur naturally and can only be produced artificially.
杂色
发表于 2025-3-28 20:11:26
Carbon Group: Elements of the Fourth Main Group,ily of elements before us..The non-metal carbon, in its graphite modification, is a high-melting solid, as are the semi-metals silicon and -with qualifications- germanium. Tin and lead, the metallic representatives of this group, on the other hand, have low melting points. Flerovium is possibly even a slightly volatile semi-metal.
obsession
发表于 2025-3-29 02:01:28
Iron Group: Elements of the Eighth Subgroup,, for ruthenium +4, for osmium and hassium +8..The discovery of iron took place as early as 3000 BC in Mesopotamia, whereas osmium and ruthenium have been found in the first half of the 19th century. The first production of hassium atoms was successful in 1984.
语源学
发表于 2025-3-29 05:55:57
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deadlock
发表于 2025-3-29 07:14:23
Alkaline Earth Metals: Elements of the Second Main Group, century. Magnesium, calcium, and barium are very common in the earth’s crust; on the other hand, beryllium and strontium are much rarer. Radium is one of the decay products of naturally occurring uranium and is therefore always present in uranium ores, albeit only in the smallest traces..The elemen
留恋
发表于 2025-3-29 14:21:10
Earth Metals: Elements of the Third Main Group, only discovered in the 19th century. Although aluminum is the most common metal, it remained hidden in elemental form for a long time. Gallium, indium, and thallium, on the other hand, are very rare..The elements of this group change their character partly strongly from semi-metal (boron) over the
者变
发表于 2025-3-29 18:42:51
Carbon Group: Elements of the Fourth Main Group,pt four electrons or usually give off two or four to achieve a stable electron configuration..Coal and thus graphite has been known since prehistoric times, and diamond as the second important modification of carbon is already mentioned in Chinese sources from the 3rd millennium BC. Since the Bronze
OVERT
发表于 2025-3-29 21:00:27
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JECT
发表于 2025-3-30 01:48:46
Chalcogens: Elements of the Sixth Main Group,nium and livermorium). Sulfur has been known for several thousand years, oxygen, selenium, and tellurium for about 200, polonium for a good 100, and livermorium for already 15 years. So, a rather “old” family of elements? Not at all. The chemistry of these substances is so extensive, there are so ma
远地点
发表于 2025-3-30 04:10:20
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