Magnesium oxide melting point

Thermal Properties. Because all limestone is converted to an oxide before fusion or melting occurs, the only melting point appHcable is that of quicklime. These values are 2570°C for CaO and 2800°C for MgO. Boiling point values for CaO are 2850°C and for MgO 3600°C. The mean specific heats for limestones and limes gradually ascend as temperatures increase from 0 to 1000°C. The ranges are as follows high calcium limestone, 0.19—0.26 dolomitic quicklime, 0.19—0.294 dolomitic limestone, 0.206—0.264 magnesium oxide, 0.199—0.303 and calcium oxide, 0.175—0.286. 

Reactant for /-butyl phenolic resins. Magnesium oxide reacts in solution with /-butyl phenolic resin to produce an infusible resinate (Fig. 36) which provides improved heat resistance. The resinate has no melting point and decomposes above 200°C. Although oxides of calcium, lead and lithium can also be used, they are not as efficient as magnesium oxide and also tend to separate from solution. Where clear adhesive solutions are required epoxide resins, zinc-calcium resinates or zinc carbonate can be used. 

Comparing the two relative forces of electrostatic attraction that you calculated, you can conclude that ionic bonding is considerably stronger in magnesium oxide. This affects the physical properties and chemical behavior of the two compounds. For example, the melting point of MgO (2,852° C) is much higher than that of LiF (845° C). 

Magnesium chromium(III) oxide crystals are deep-green octa-hedra possessing the normal, cubic, spinel structure, a0 = 8.335 A., and having a melting point of approximately 2390°C. 

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