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- Helium-3 | chemical isotope | Britannica
Helium-3 is a trace element in the solar wind, and the lunar surface has absorbed larger quantities of helium-3 than have been found on Earth If mining on the Moon ever becomes practical, helium-3 would be a valuable fuel for nuclear fusion power
- Chemical reaction | Definition, Equations, Examples, Types - Britannica
A chemical reaction is a process in which one or more substances, the reactants, are converted to one or more different substances, the products Substances are either chemical elements or compounds
- Chemical compound | Definition, Examples, Types | Britannica
Chemical compound, any substance composed of identical molecules consisting of atoms of two or more chemical elements All the matter in the universe is composed of the atoms of more than 100 different chemical elements, which are found both in pure form and combined in chemical compounds
- Sodium bicarbonate | Definition, Uses, Formula | Britannica
sodium bicarbonate (NaHCO3), white crystalline or powdery solid that is a source of carbon dioxide and so is used as an ingredient in baking powders, in effervescent salts and beverages, and as a constituent of dry-chemical fire extinguishers
- Chemical energy | Definition Facts | Britannica
The chemical energy in food is converted by the body into mechanical energy and heat The chemical energy in coal is converted into electrical energy at a power plant The chemical energy in a battery can also supply electrical power by means of electrolysis
- Gallium | Uses, Properties, Facts | Britannica
Gallium, chemical element of Group 13 (the boron group) of the periodic table It liquefies just above room temperature Gallium compounds, some of which form the basis for light-emitting diodes (LEDs), have valuable semiconductor and optoelectronic properties
- Sodium - Chemical Properties, Reactions, Uses | Britannica
Substances are either chemical elements or compounds A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products Chemical reactions are an integral part of technology, of culture, and indeed of life itself
- Silver | Facts, Properties, Uses | Britannica
Silver, chemical element of atomic number 47, a white lustrous metal valued for its decorative beauty and electrical conductivity Silver’s physical and chemical properties are intermediate between those of copper and gold It is located in Group 11 of the periodic table
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