Stability with ammonia over

A (not-closed) heated solution of ammonia gradually loses ammonia. If a cation is complexed with ammonia, the free-cation concentration will gradually increase as ammonia is lost (a rare example of slow cation release rather than anion release). It will also increase with an increase in temperature, due to the decrease in stability of complexes with increasing temperature. As one example using this principle, thin films of mixed ZnO/Zn(OH)2, which converted to ZnO on heating over 200°C, were deposited from a heated aqueous Zn-ion/ammonia bath. 

It is instructive to compare the copper-ammonia and the copper-ethylenediamine systems. The greater stability of chelates over simple coordination compounds is dramatically seen in the much lower en concentration, 10 M, as compared to 10 M for NHj, at which the free copper ion concentration begins to fall. It will also be observed that the greater separation of the stepwise constants than is observed with simple... 

A fraction of nitric acid in the troposphere becomes associated with aerosol particles and forms particulate nitrates. The interaction of HNO3 with virgin sea salt particles stabilizes nitric acid in the form of sodium nitrate, NaN03. Over the continents, the interaction with ammonia leads to the formation of solid ammonium nitrate, NH4NO3. This compound exists in a temperature-dependent equilibrium... 

There is reeent evidenee that stabilization to elevated temperatures (over 350°C) yields a strueture with additional intermoleeular eross-linking that results in improved mechanieal properties in earbonized fibers [10,11]. In addition, it has been noted that the addition of ammonia to the stabilizing environment aeeelerates stabilization [12]. 

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