Magnesium fluoride, formation

For example, in the formation of magnesium fluoride by combination of magnesium and fluorine magnesium is the reducing agent and fluorine is the oxidizing agent ... 

We have discussed the formation of sodium chloride before and have noted that it is an oxidation-reduction reaction uncharged sodium atoms lose electrons to form Na ions, and uncharged chlorine atoms gain electrons to form Cl ions. The synthesis of magnesium fluoride is also an oxidation-reduction reaction because Mg and F ions are produced from the uncharged atoms. 

Thermochemistry, When 2.000 g of magnesium is burned in fluorine to magnesium fluoride at constant pressure, 44.75 kcal are evolved. Calculate AHi, the molar heat of formation of MgF2(c). 

The main purpose of the preflush is to dissolve carbonate minerals in the formation prior to injection of the main HF mixture. HF reacts with carbonates, such as calcium carbonate and magnesium carbonate, to form insoluble calcium and magnesium fluorides. If a separate water displacement stage is not employed, the acid preflush serves the additional purpose of displacing formation water from the main HF stage. If given the opportunity, spent HF will react with sodium, potassium, and calcium ions in formation brine to form insoluble precipitates that can cause severe plugging in the formation. 

W.P. Hsua, Q. Zhong and E. Matijevic, The Formation of uniform colloidal particles of magnesium fluoride and sodium magnesium fluoride, J. Colloid Interf. Sci., 181, 142-148 (1996). 

Formation of aryl Grignard reagents (Section 14 4) Aryl halides react with magnesium to form the corresponding arylmagnesium halide Aryl iodides are the most reac tive aryl fluorides the least A similar reaction occurs with lithium to give aryllithium reagents (Section 14 3)... 

Significant vapor pressure of aluminum monofluoride [13595-82-9], AIF, has been observed when aluminum trifluoride [7784-18-1] is heated in the presence of reducing agents such as aluminum or magnesium metal, or is in contact with the cathode in the electrolysis of fused salt mixtures. AIF disproportionates into AIF. and aluminum at lower temperatures. The heat of formation at 25°C is —264 kJ/mol(—63.1 kcal/mol) and the free energy of formation is —290 kJ/mol(—69.3 kcal/mol) (1). Aluminum difluoride [13569-23-8] h.3.s been detected in the high temperature equihbrium between aluminum and its fluorides (2). 

BeryUium reacts with fused alkaU haUdes releasing the alkaU metal until an equUibrium is estabUshed. It does not react with fused haUdes of the alkaline-earth metals to release the alkaline-earth metal. Water-insoluble fluoroberyUates, however, are formed in a fused-salt system whenever barium or calcium fluoride is present. BeryUium reduces haUdes of aluminum and heavier elements. Alkaline-earth metals can be used effectively to reduce beryUium from its haUdes, but the use of alkaline-earths other than magnesium [7439-95-4] is economically unattractive because of the formation of water-insoluble fluoroberyUates. Formation of these fluorides precludes efficient recovery of the unreduced beryUium from the reaction products in subsequent processing operations. 

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