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21 小時前 · Hydrogen peroxide is a chemical compound with the formula H 2 O 2. In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
- H₂O₂
- 34.014 g·mol−1
- −0.43 °C (31.23 °F; 272.72 K)
- Miscible
3 天前 · List of chemical elements. As of April 2024, 118 chemical elements have been identified and named officially by IUPAC. A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z ). [1]
3 天前 · ASCII (/ˈæskiː/ ⓘ ASS-kee),[3]: 6 an acronym for American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because of technical limitations of computer systems at the time it was invented ...
2 天前 · Graphene is an atomic-scale hexagonal lattice made of carbon atoms. Graphene ( / ˈɡræfiːn / [1]) is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice [2] [3] nanostructure. [4] The name is derived from "graphite" and the suffix -ene, reflecting the fact that the graphite allotrope of ...
3 天前 · Estimated to have employed over 100 scholars at its height [8] [9] The Great Library of Alexandria in Alexandria, Egypt, was one of the largest and most significant libraries of the ancient world. The library was part of a larger research institution called the Mouseion, which was dedicated to the Muses, the nine goddesses of the arts. [10]
21 小時前 · In astronomy, dark matter is a hypothetical form of matter that appears not to interact with light or the electromagnetic field. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be seen.
1 天前 · Godzilla ( Japanese: ゴジラ, Hepburn: Gojira) is a Japanese monster, or kaiju, media franchise consisting of films, television series, novels, comic books, video games, and other merchandise. The franchise is centered on the fictional kaiju Godzilla, a prehistoric reptilian monster awakened and powered by nuclear radiation.
