Search results
Results from the WOW.Com Content Network
Water-reactive substances[ 1 ] are those that spontaneously undergo a chemical reaction with water, often noted as generating flammable gas. [ 2 ] Some are highly reducing in nature. [ 3 ] Notable examples include alkali metals, lithium through caesium, and alkaline earth metals, magnesium through barium. Some water-reactive substances are also ...
The electrolysis of water in standard conditions requires a theoretical minimum of 237 kJ of electrical energy input to dissociate each mole of water, which is the standard Gibbs free energy of formation of water. It also requires thermal energy to balance the change in entropy of the reaction.
Chemical reaction. A thermite reaction using iron (III) oxide. The sparks flying outwards are globules of molten iron trailing smoke in their wake. A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. [ 1 ] When chemical reactions occur, the atoms are rearranged and the ...
In liquid form, H2O is also called "water" at standard temperature and pressure. Because Earth's environment is relatively close to water's triple point, water exists on Earth as a solid, a liquid, and a gas. [ 22 ] It forms precipitation in the form of rain and aerosols in the form of fog.
Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom H and a chlorine atom Cl connected by a polar covalent bond. The chlorine atom is much more electronegative than the hydrogen atom, which makes this bond polar. Consequently, the molecule has a large dipole moment with a negative partial charge (δ−) at the chlorine atom ...
Sublimation of iodine. Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. [1] The verb form of sublimation is sublime, or less preferably, sublimate. [2] Sublimate also refers to the product obtained by sublimation. [2][3] The point at which sublimation occurs rapidly ...
Helium is the least water-soluble monatomic gas, [95] and one of the least water-soluble of any gas (CF 4, SF 6, and C 4 F 8 have lower mole fraction solubilities: 0.3802, 0.4394, and 0.2372 x 2 /10 −5, respectively, versus helium's 0.70797 x 2 /10 −5), [96] and helium's index of refraction is closer to unity than that of any other gas. [97]
In physics, chemistry, and other related fields like biology, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states of matter: solid, liquid, and gas, and in rare cases, plasma.