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|Section2= |Section3= |Section4= |Section7= |Section8= }} Caesium fluoride or cesium fluoride is an inorganic compound usually encountered as a hygroscopic white solid. It is used in organic synthesis as a source of the fluoride anion. Caesium has the lowest electronegativity of all non-radioactive elements and fluorine has the highest electronegativity of all elements. ==Synthesis and properties== Caesium fluoride can be prepared by the reaction of caesium hydroxide (CsOH) with hydrofluoric acid (HF). The resulting salt can then be purified by recrystallization. The reaction is shown below: :CsOH(aq) + HF(aq) → CsF(aq) + H2O(l) Another way to make caesium fluoride is to react caesium carbonate (Cs2CO3) with hydrofluoric acid. The resulting salt can then be purified by recrystallization. The reaction is shown below: :Cs2CO3(aq) + 2 HF(aq) → 2 CsF(aq) + H2O(l) + CO2(g) In addition, elemental fluorine and caesium can be used to form caesium fluoride as well, but doing so is very impractical because of the expense.〔(Reacting Fluorine with Caesium ). Youtube〕 While this is not a normal route of preparation, caesium metal reacts vigorously with all the halogens to form caesium halides. Thus, it burns with fluorine gas, F2, to form caesium fluoride, CsF according to the following reaction: :2 Cs(s) + F2(g) → 2 CsF(s) CsF is more soluble than sodium fluoride or potassium fluoride. It is available in anhydrous form, and if water has been absorbed it is easy to dry by heating at 100 °C for two hours ''in vacuo''. CsF reaches a vapor pressure of 1 kilopascal at 825 °C, 10 kPa at 999 °C, and 100 kPa at 1249 °C. CsF chains with a thickness as small as one or two atoms can be grown inside carbon nanotubes.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「caesium fluoride」の詳細全文を読む スポンサード リンク
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