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1 天前 · Structure and name. The molecule adopts a tetrahedral molecular geometry with C 3v symmetry. [14] . The chloroform molecule can be viewed as a methane molecule with three hydrogen atoms replaced with three chlorine atoms, leaving a single hydrogen atom.
4 天前 · Sulfuric acid ( American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling ), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, and hydrogen, with the molecular formula H2SO4. It is a colorless, odorless, and viscous liquid that is miscible with water. [6]
3 天前 · Blue light is scattered more than other wavelengths by the gases in the atmosphere, surrounding Earth in a visibly blue layer at the stratosphere, above the clouds of the troposphere, when seen from space on board the ISS at an altitude of 335 km (208 mi) (the Moon is visible as a crescent in the far background).[1] The atmosphere of Earth is ...
2 天前 · Renewable energy (or green energy) is energy from renewable natural resources that are replenished on a human timescale. The most widely used renewable energy types are solar energy, wind power and hydropower. Bioenergy and geothermal power are also significant in some countries.
1 天前 · Mercury is the first planet from the Sun and the smallest in the Solar System. In English, it is named after the ancient Roman god Mercurius ( Mercury ), god of commerce and communication, and the messenger of the gods. Mercury is classified as a terrestrial planet, with roughly the same surface gravity as Mars.
2 天前 · The swastika ( 卐 or 卍) is an ancient religious and cultural symbol, predominantly found in various Eurasian cultures, as well as some African and American ones. In the western world it is more widely recognized as a symbol of the German Nazi Party who appropriated it from Asian cultures starting in the early 20th century.
3 天前 · The koala ( Phascolarctos cinereus ), sometimes called the koala bear, is an arboreal herbivorous marsupial native to Australia. It is the only extant representative of the family Phascolarctidae and its closest living relatives are the wombats.
