Atomistry » Magnesium » Chemical Properties » Magnesium Nitrate
Atomistry »
  Magnesium »
    Chemical Properties »
      Magnesium Nitrate »

Magnesium Nitrate, Mg(NO3)2

Metallic magnesium, magnesia, and magnesium carbonate dissolve easily in nitric acid to magnesium nitrate. From neutral solutions at ordinary temperatures the hexahydrate, Mg(NO3)2.6H2O, crystallises in monoclinic prisms and needles which do not effloresce over sulphuric acid. Mg(NO3)2.9H2O forms when the solution is cooled to -20° C.; at -17° C. it reverts to the hexahydrate.

The heat of solution of the hexahydrate is -4.200 Cal.; it melts in its water of crystallisation, and with rising temperature loses water and, apparently, nitric acid. The basic salts 3MgO.2N2O5.5H2O and 4MgO.N2O5 have been said to result from this double loss.

According to Lescoeur, the hexahydrate gradually dissociates into the trihydrate at 65° C., and the latter also results when a saturated, neutral solution of magnesium nitrate is mixed with an equal volume of fuming nitric acid. Ditte, by heating the hexahydrate, obtained a syrupy mass which suddenly solidified into the trihydrate. He also obtained transparent prisms of the dihydrate by heating the nitrate till nitric oxide began to come off, dissolving in nitric acid, and crystallising. The crystals were very deliquescent.

Magnesia is the final product of heat upon magnesium nitrate: according to Graham, the monohydrate is formed at the temperature of melting lead.

A nearly saturated solution of magnesium nitrate evolves heat on dilution. A saturated aqueous solution of magnesium nitrate at 0° C. contains 39.96 per cent, of the anhydrous salt.

Mg(OH)2+2HNO3Aq. = Mg(NO3)2Aq.+27.600 Cal.

Didier obtained 3MgO.N2O5.5H2O in slender, white, microscopic needles, which were optically active, by treating a solution of magnesium nitrate at 100° C. with small quantities of magnesium at a time, heating to 150° C., filtering through cloth, and allowing to stand in a closed vessel. It was decomposed by water and alcohol.

Last articles

Zn in 8WB0
Zn in 8WAX
Zn in 8WAU
Zn in 8WAZ
Zn in 8WAY
Zn in 8WAV
Zn in 8WAW
Zn in 8WAT
Zn in 8W7M
Zn in 8WD3
© Copyright 2008-2020 by atomistry.com
Home   |    Site Map   |    Copyright   |    Contact us   |    Privacy