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For many substances, the formation reaction may be considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction can then be analyzed by applying Hess' law, which states that the sum of the enthalpy changes for a number of individual reaction steps equals the enthalpy change of the overall reaction.
A single-displacement reaction, also known as single replacement reaction or exchange reaction, is an archaic concept in chemistry. It describes the stoichiometry of some chemical reactions in which one element or ligand is replaced by an atom or group. [1] [2] [3] It can be represented generically as: + +
Reaction times tend to be on the order of hours and yields are moderate. [7] Fluorination of lactones can provide heterocyclic fluorides, although ring opening has been observed for γ-butyrolactone. The six-membered lactide does not experience ring opening. [8] Fluorination opens epoxides to give either geminal or vicinal difluorides in most ...
Reactions of elemental fluorine with metals require varying conditions. Alkali metals cause explosions and alkaline earth metals display vigorous activity in bulk; to prevent passivation from the formation of metal fluoride layers, most other metals such as aluminium and iron must be powdered, [ 21 ] and noble metals require pure fluorine gas ...
The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).
Reaction can be written as: 2 Ca(AsF 6) 2 + 9 XeF 2 → Ca 2 (XeF 2) 9 (AsF 6) 4. This reaction requires a large excess of xenon difluoride. The structure of the salt is such that half of the Ca 2+ ions are coordinated by fluorine atoms from xenon difluoride, while the other Ca 2+ ions are coordinated by both XeF 2 and AsF − 6.
The associated free energy change of the reaction is composed of the changes of two different thermodynamic quantities, enthalpy and entropy: [17] =. G: free energy, H: enthalpy, T: temperature, S: entropy, Δ: difference (change between original and product)
Oxygen difluoride reacts with water to form hydrofluoric acid: OF 2 + H 2 O → 2 HF + O 2. It can oxidize sulphur dioxide to sulfur trioxide and elemental fluorine: OF 2 + SO 2 → SO 3 + F 2. However, in the presence of UV radiation, the products are sulfuryl fluoride (SO 2 F 2) and pyrosulfuryl fluoride (S 2 O 5 F 2): OF 2 + 2 SO 2 → S 2 O ...