These are also acidic, and can lose hydrogen ions from another of the water ligands. Whichever of the above reactions happens, you end up with + ions in solution. Notice that this is still a reversible change (unlike the corresponding change when you add hydroxide ions). If that happens, you get exactly the same new complex ion formed as above.

There are far more hexaaqua ions present. Statistically, there is far more chance of an ammonia molecule hitting a hexaaqua metal ion than of hitting a hydrogen ion. Reaction of ammonia with the hexaaqua ion Use the BACK button on your browser to return quickly to this page. Note: You really need to know about Le Chatelier's Principle, particularly with regard to the effect of changes in concentration on the position of equilibrium. Reaction of ammonia with the hydroxonium ions (hydrogen ions)Īmmonia will react with these to produce ammonium ions.Īccording to Le Chatelier's Principle, the position of equilibrium will move to the right, producing more of the new complex ion. They are acting as acids by donating hydrogen ions to water molecules in the solution.īecause of the confusing presence of water from two different sources (the ligands and the solution), it is easier to simplify this:Īdding ammonia solution to this equilibrium - stage 1 Their acidity is shown in the reaction of the hexaaqua ions with water molecules from the solution: These have the formula 2+, and they are acidic. We'll talk through what happens if you add a small amount of dilute ammonia solution to a solution containing a 2+ hexaaqua ion. The ligand effect only happens with an excess of ammonia or with concentrated ammonia - and with some metals you don't even see it then. This is what happens when you only add small amounts of dilute ammonia solution to any of the hexaaqua ions. Use the BACK button on your browser to return to this page when you are confident about these terms.Īmmonia acting as a (Bronsted-Lowry) base Note: If you aren't familiar with either of these terms, you should follow this link to a page about theories of acids and bases. We need to look at these two functions separately. When it acts as a ligand, it is acting as a Lewis base. It can act as a base (in the Bronsted-Lowry sense), but it is also a possible ligand which can replace water molecules around the central metal ion. Reactions of the hexaaqua ions with ammonia solution are complicated by the fact that the ammonia can have two quite different functions. It will probably be easiest to return to this page via the complex ions menu.

The present page draws information from all of these pages, and you will find it easier to understand if you spend some time reading these other pages first. It would also be useful to read two more pages: the one describing the reactions of these ions with hydroxide ions, and the one explaining ligand exchange reactions. Important: Before you read this page, you need to know about the acidity of the hexaaqua ions. This page describes and explains the reactions between complex ions of the type n+ and ammonia solution. REACTIONS OF HEXAAQUA METAL IONS WITH AMMONIA SOLUTION Reactions of aqua ions with ammonia solution

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