Sciencemadness Discussion Board

Uses for nickel (II) perchlorate hexahydrate

B(a)P - 19-8-2020 at 02:04

A not so recent purchase has recently arrived including, among other chemicals, some nickel (II) nitrate hexahydrate. What actually showed up was nickel (II) perchlorate hexahydrate. I have done some searching and can't find much about the compound (that is of interest to the hobby chemist). Would it be sacrilegious to add it to a solution of potassium nitrate to convert it to nickel nitrate and potassium perchlorate? Is there anything of interest that I am missing? Thanks in advance for any input.

Lion850 - 19-8-2020 at 03:25

In case you want to buy nickel nitrate (again) and not convert the perchlorate, Vanbar sells it for around AUD 25 for 250g.

symboom - 19-8-2020 at 05:29

You could make Tetraminenickel perchlorate it looks purple acts like 'black powder'

B(a)P - 19-8-2020 at 13:45

Thanks Lion850, I had not found nickel nitrate at a reasonable price in Australia.
I will give tetraamine nickel perchlorate a go thanks symboom, it looks like a pretty and interesting compound.

Just trying to plan out the reaction. That video you provided the link for symboom said it is a synthesis for hexaaminenickel perchlorate. Did you mean tetra or hexa? Also the video claims the formula for the product is [Ni[NH3]6](ClO4)2, shouldn't it be [Ni[NH2]6](ClO4)2?

[Edited on 20-8-2020 by B(a)P]

woelen - 19-8-2020 at 23:08

If you really have nickel perchlorate, then you have a very interesting chemical. You can make numerous metal complexes, which crystallize really well.

One experiment you can do is adding excess ammonia to a solution of nickel perchlorate. This will give you a very fine blue precipitate of Ni(NH3)6(ClO4)2. This compound is stable and can be stored indefinitely, but when it is heated it decomposes with appearance of fire. It burns like black powder on ignition. This compound has fuel (ammonia) and oxidizer (perchlorate) in one.

Other compounds, which can be made, are nickel(en)3(ClO4)2. Here (en) stands for ethylene diamine. A similar complex can be made with diethylene triamine. You can also make complexes with other amines, with pyridine and with hydrazine (the latter is quite dangerous, only make small amounts, because the nickel hydrazine perchlorate is quite sensitive and can explode on too strong mechanical agitation).

See here:

I definitely would not convert the nickel perchlorate to nickel nitrate. The latter is much more common and easier to obtain. Getting the perchlorate is not easy. I made it myself from nickel oxide and perchloric acid for certain experiments, but perchloric acid also is not that easily obtained in most countries. For the experiment in the link above, I used a mix of ammonium perchlorate and nickel nitrate.

B(a)P - 20-8-2020 at 02:13

Thanks very much woelen I will give these reactions a go.
A couple of questions if I may?
I am trying to understand the reaction for the synthesis of Ni(NH3)6(ClO4)2. Does the nickel ion, acting as a central, offer up 6 pairs of electrons for complexing with the L ligand ammonia? Is the nickel reduced such that it will now accomodate two perchlorate ions, and if so what is the oxidant?
Ethylenediamine does not seem to be easy to source. It also seems pretty challenging to synthesise, 1,2DCE under pressure at 180C. Did you make yours or purchase it? Are there easier routes to this synthesis?

woelen - 20-8-2020 at 04:39

The nickel does not offer 6 electron pairs, but it accepts 6 electron pairs. It is a Lewis acid. The ammonia acts as Lewis base. It has a lone pair of electrons, which are shared with the nickel ion. The nickel is not reduced, nor oxidized. It is in oxidation state +2 and remains in oxidation state +2 in the ammonia complex. The perchlorate ion does not react in this reaction, it is just a counter ion with which the nickel-ammonia complex forms a sparingly soluble compound, which precipitates from the solution (it is one of the perchlorates with very low solubility, even much lower than the solubility of KClO4 and CsClO4).

Where I live, ethylenediamine is easy to obtain. It is not restricted or watched. I purchased it.

One seller with decent prices:

I'm not sure though to which countries this seller ships.

B(a)P - 20-8-2020 at 13:45

Thanks again woelen! I have tried many of the reactions that you have on your web site, there is a lot of great material in there!
My confusion around the oxidation state came about because I had thought that nickel was in the +1 oxidation state as NiClO4, but I now realise nickel perchlorate is is Ni(ClO4)2.
I will try this complex over the weekend and report back.

B(a)P - 23-8-2020 at 15:50

1 g of Ni(ClO4)2.6H2O was dissolved in 10 mls of dH2O at room temperature.
10 mls of 30% ammonia solution was then added slowly, no change in temperature was observed.
The solution changed to a deep blue colour and a dark blue precipitate was observed.
The solution was gravity filtered and the crystalline solid left to air dry for 24 hours following washing with dH2O.
Once dry the crystalline solid became a lavender colour.
The yield was approximately 0.95 g of Ni(NH3)6(ClO4)2 [about 96% based on Ni(ClO4)2.6H2O].
When a small portion (~50 mg) is heated directly or indirectly with a propane torch the product burns rapidly.
When struct hard with a hammer the product detonates.
The product seems insensitive to friction.
When a small portion (~100 mg) is heated confined in aluminium foil it detonates.
All in all an interesting and pretty compound.

Lion850 - 23-8-2020 at 19:20

B(a)P sounds cool I'll add this syntheses to the ever growing list of experiments I would like to do. .

B(a)P - 25-8-2020 at 01:50

Quote: Originally posted by fusso  
Quote: Originally posted by B(a)P  
The solution changed to a deep blue colour and a dark blue precipitate was observed.
The solution was gravity filtered and the crystalline solid left to air dry for 24 hours following washing with dH2O.
Dont you need to convert all Ni(OH)2 into Ni(NH3)6 2+?

I am not sure I understand the question. What do you mean by Ni(OH)2?

fusso - 25-8-2020 at 03:40

Quote: Originally posted by B(a)P  
I am not sure I understand the question. What do you mean by Ni(OH)2?
Oh nevermind, shouldnt have asked that.

woelen - 26-8-2020 at 04:47

Good to see that you did the experiment with the hexamminenickel(II) complex. The perchlorate of this indeed is quite an interesting compound. It also is interesting to see how this complex behaves on slow addition of acid. You then get a reverse reaction in which the lavender material changes back to green nickel(II), through different shades of blue and cyan. Once you have done that experiment, you can get your hexammine complex back by adding excess ammonia, which reprecipitates the complex.