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History of electrochemistry. Electrochemistry, a branch of chemistry, went through several changes during its evolution from early principles related to magnets in the early 16th and 17th centuries, to complex theories involving conductivity, electric charge and mathematical methods. The term electrochemistry was used to describe electrical ...
In the original 1952 experiment, methane (CH 4), ammonia (NH 3), and hydrogen (H 2) were all sealed together in a 2:2:1 ratio (1 part H 2) inside a sterile 5-L glass flask connected to a 500-mL flask half-full of water (H 2 O). The gas chamber was intended to represent Earth's prebiotic atmosphere, while the water simulated an ocean. The water ...
Dehydrogenation. In chemistry, dehydrogenation is a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. At its simplest, it's a useful way of converting alkanes, which are relatively inert and ...
Oxygen began building up in the atmosphere at approximately 1.85 Ga. At current rates of primary production, today's concentration of oxygen could be produced by photosynthetic organisms in 2,000 years. [ 4] In the absence of plants, the rate of oxygen production by photosynthesis was slower in the Precambrian, and the concentrations of O 2 ...
Mineral evolution. Most minerals on Earth formed after photosynthesis by cyanobacteria (pictured) began adding oxygen to the atmosphere. Mineral evolution is a recent hypothesis that provides historical context to mineralogy. It postulates that mineralogy on planets and moons becomes increasingly complex as a result of changes in the physical ...
Metastable metallic hydrogen may have potential as a highly efficient rocket propellant; the metallic form would be stored, and the energy of its decompression and conversion to the diatomic gaseous form when released through a nozzle used to generate thrust, with a theoretical specific impulse of up to 1700 seconds (for reference, the current ...
The history of glass-making dates back to at least 3,600 years ago in Mesopotamia. However, most writers claim that they may have been producing copies of glass objects from Egypt. [ 1] Other archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or Egypt. [ 2]
Cavendish discovered hydrogen as a colorless, odourless gas that burns and can form an explosive mixture with air, and published a paper on the production of water by burning inflammable air (that is, hydrogen) in dephlogisticated air (now known to be oxygen), the latter a constituent of atmospheric air (phlogiston theory).