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1 天前 · Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the formula N H 3.A stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers.
- NH₃
- 47% w/w (0 °C), 31% w/w (25 °C), 18% w/w (50 °C)
- 17.031 g·mol−1
- −77.73 °C (−107.91 °F; 195.42 K) (Triple point at 6.060 kPa, 195.4 K)
2 天前 · Michael Joseph Jackson (August 29, 1958 – June 25, 2009) was an American singer, songwriter, dancer, and philanthropist. Known as the "King of Pop", he is regarded as one of the most significant cultural figures of the 20th century. During his four-decade career, his contributions to music, dance, and fashion, along with his publicized ...
2 天前 · Common side effects of nicotine use according to route of administration and dosage form Route of administration Dosage form Associated side effects of nicotine Sources Buccal Nicotine gum Indigestion, nausea, hiccups, traumatic injury to oral mucosa or teeth, irritation or tingling of the mouth and throat, oral mucosal ulceration, jaw-muscle ache, burping, gum sticking to teeth, unpleasant ...
3 天前 · The BBC is a state owned public broadcasting company and operates under a royal charter.The charter is the constitutional basis for the BBC, and sets out the BBC's Object, Mission and Public Purposes. It emphasises public service, (limited) editorial independence, prohibits advertising on domestic services and proclaims the BBC is to "seek to avoid adverse impacts on competition which are not ...
2 天前 · The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
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. The surface of Mercury is heavily ...
2 天前 · Venus is the second planet from the Sun. It is a terrestrial planet and is the closest in mass and size to its orbital neighbour Earth. Venus is notable for having the densest atmosphere of the terrestrial planets, composed mostly of carbon dioxide with a thick, global sulfuric acid cloud cover. At the surface it has a mean temperature of 737 ...
