Hydrogen calcium

When heated in the presence of magnesium and hydrogen, calcium carbonate gives rise to a highly violent reaction. 

The solvent had been dried over the aluminate and then stored over calcium hydride for 2 years to prevent peroxide formation . Subsequent addition of more aluminate caused a strong exotherm and ignition of liberated hydrogen. Calcium hydride does not prevent peroxide formation in solvents. 

As seen in Table 2.7, the lower the pH, the greater quantity of calcium ions dissolved. The dissolved calcium ions are substituted by hydrogen ions in the interlayer space. In other words, the cations in the interlayer space of montmorillonite react with water itself, and a hydrogen-calcium cation-exchange reaction takes place ... 

These are crystalline compounds made by heating the metal in hydrogen calcium, for instance, reacts at 150°. Those of the alkali metals, XH, have the sodium chloride type lattice (p. 141) those of the Gp. IIA metals are less regular. All have stoichiometric compositions and the crystals are ionic, being somewhat denser than the metal from which they are made owing to the strong polar bonds in the ionic lattice. 

Rufyikiri, G., Genon, J.G., Dufey, J.E., Delvaux, B., 2003. Competitive adsorption of hydrogen, calcium, potassium, magnesium, and aluminum on banana roots experimental data and modeling. J. Plant Nutr. 26, 351-368. 

A. Sibbald, P.D. Whalley, A.K. Covington, A miniature flow-through cell with a four-function ChemP T integrated circuit for simultaneous measurements of potassium, hydrogen, calcium and sodium ions. Anal. Chim. Acta 1984 159 47-62. 

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