Sciencemadness Discussion Board

silver chemistry

bismuthate - 28-9-2013 at 05:16

i just recived 25g of silver nitrate and i want to make unusual and exotic silver compounds with it. i've tried making silver permanganate, but i was wondering if it is possible to make silver manganate by mixing potassium manganate and silver nitrate or would the silver nitrate oxidise the manganate?

sonogashira - 28-9-2013 at 06:06

Have you looked in Inorganic Syntheses? Silver chemistry is very well researched.

bismuthate - 28-9-2013 at 06:10

yes but i found nothing on silver manganate. does it even exist?

Hegi - 28-9-2013 at 07:22

I have a lot of silver nitrate so I am interested in this topic as well.. Would be great if you came up with something interesting and gave some tips.. :)

BobD1001 - 28-9-2013 at 08:23

A couple of fun experiments that I know of with Silver nitrate are making a silver mirror in a test tube, and also the classic silver acetylide double salt. Be very careful with the silver acetylide though, limit the reaction to a couple hundred milligrams at most, as it can be pretty scary stuff.

bismuthate - 28-9-2013 at 08:32

yeah i was also wonderiing what coumpounds i could percipitate. ex silver chromate, chloride, iodide etc. but is silver manganate possible?

bismuthate - 28-9-2013 at 08:37


bobd1001 yes i can be scary if you bump it will explode easily, but if handeled with proper precautions it can be rather harmless due to a lack of gaseos products :). also i want realy unique compoands like silver aluminate or silicate


[Edited on 28-9-2013 by bismuthate]

blogfast25 - 28-9-2013 at 09:34

Quote: Originally posted by bismuthate  
yeah i was also wonderiing what coumpounds i could percipitate. ex silver chromate, chloride, iodide etc. but is silver manganate possible?


Assuming you mean silver permanganate (not manganite VI) then according to Wikipedia, yes:

http://en.wikipedia.org/wiki/Silver_permanganate

It would be synthesised by using AgMnO4's poor solubility in cold water (0.55 g/100 ml at 0 C, acc. Wiki). Mix fairly concentrated solutions of KMnO4 and AgNO3, then chill to obtain the AgMnO4.

Photos would be nice.


[Edited on 28-9-2013 by blogfast25]

bismuthate - 28-9-2013 at 09:53

no actualy i was talking about mangante as in the ion you get from decomposing potassium permanganate, but i plan to make silver permanganate too

chornedsnorkack - 28-9-2013 at 12:37

In aqueous conditions, manganates are stable in basic conditions.

What is the pH where manganate dismutes, and what is the pH where Ag precipitates?

bismuthate - 28-9-2013 at 13:07

i'm not sure but i plan to find out soon.
i made agkmno4 which is an unimpessive gray powder.
i will make silver borate in the next 10 mins.

sonogashira - 28-9-2013 at 13:13

Brauer says that it forms black lustrous needles. See page 1463:
http://books.google.co.uk/books?hl=en&lr=&id=Pef47TK...

bismuthate - 28-9-2013 at 13:28

sonogashira: odd, that had the same formula as the permanganate what does that mean? could they have described the permangante with a different name?
i made silver borate it is a brown insoluable powder. it looks nothing like i expected.
i think i"ll combine sodium zincate with silver nitrate and see the results.

bismuthate - 29-9-2013 at 04:35

actualy i'm not sure what it is but it came from mixing AgNO3 and borax what is this?

blogfast25 - 29-9-2013 at 05:46

Quote: Originally posted by bismuthate  
actualy i'm not sure what it is but it came from mixing AgNO3 and borax what is this?


Your supposition that it is silver borate may be plain wrong: borax solutions are very alkaline, silver oxide/hydroxide is thus likely to precipitate instead of silver borate. The colour certainly matches that of silver oxide/hydroxide.

You can't just mix things together and hope for the best without taking into account that some of it will in fact react with the solvent (water): see hydrolysis of borates....

bismuthate - 29-9-2013 at 05:51

sorry. i plan to test it by adding ammonia

blogfast25 - 29-9-2013 at 06:10

Quote: Originally posted by bismuthate  
sorry. i plan to test it by adding ammonia


You mean ammonia solution. That of course contains loads of water too.

But ammonia is generally a very bad idea with Ag+ because it forms a complex with ammonia: [Ag(NH3)2]+ cations. The complex is so strong that the insoluble AgCl dissolves in strong ammonia solutions!

If you take your brown precipitate that you mentioned upthread and add strong ammonia solution to it, chances are the precipitate will dissolve by the formation of this complex.

Also, read up about the dangers of this complex.


[Edited on 29-9-2013 by blogfast25]

sonogashira - 29-9-2013 at 06:11

In fact the preparation using a borax solution is correct. Surely there is a better reference, but this will do, p625: http://books.google.co.uk/books?id=P_MVjTFh16YC&pg=PA625...

blogfast25 - 29-9-2013 at 06:15

It's possible Sono, at least there are plenty references to the term 'silver borate'. But one mustn't a priori assume that this salt or that salt is formed when hydrolysis is in play.

[Edited on 29-9-2013 by blogfast25]

bismuthate - 29-9-2013 at 06:52

thats interesting. both AgNO3 and borax are soluble in glycerin so maybe i could avoid hydrolysis by having no water present in the reaction. although the borax would need to be anhydrous. would this work or am i missing something obvious? (i have a feeling i am)

bfesser - 29-9-2013 at 07:11

You are: <a href="https://en.wikipedia.org/wiki/Glycerol" target="_blank">glycerin</a> <img src="../scipics/_wiki.png" /> is hygroscopic. Ignoring the rest of the chem, you're unlikely to have dry glycerin.

bismuthate - 29-9-2013 at 07:18

this has already gone beyond what i plan to do at home. now i just want to know theoreticly, could one do this?

bismuthate - 29-9-2013 at 07:21

is there anything else both are soluble in? also it doesn't matter much if there is a bit of water as long as it's mostly water free.

[Edited on 29-9-2013 by bismuthate]

blogfast25 - 29-9-2013 at 07:28

One way of verifying your precipitate is indeed silver borate would be to filter and wash it, then transfer the filter cake to a separate beaker and add strong HCl to it. The brown precipitate should convert to a white one and flakes of boric acid should be observed, after standing for a bit:

Silver borate (precipitate) + HCl (solution) === > AgCl (white precipitate) + B(OH)3 (oily flakes)

bismuthate - 29-9-2013 at 07:37

it worked i have silver borate!:D

bismuthate - 29-9-2013 at 07:52

anything you think i should synthesise? (citrate aluminate asprinate etc)

blogfast25 - 29-9-2013 at 07:58

Quote: Originally posted by bismuthate  
it worked i have silver borate!:D


Hmmm... for your credibility it helps if you describe concisely what you actually did and what you observed. This is a science forum: we're naturally sceptical. Others could be interested in preparing silver borate too, and they'll want as much information as possible with regards to your experiments.

bismuthate - 29-9-2013 at 08:13

ok
so i took a small amount of very fine silver borate powder (about 0.2 grams) and placed it in a 100ml flask then i added three drops of HCl and imediatly, i was suprised haw fast, the brown powder turned into white powder (there was slightly more white powder) that easily floated about in the water.
sorry about not explaining before, i know that you have reason to be sceptical because thats part of science plus i'm new here.

Nicodem - 29-9-2013 at 08:32

The preparation of silver and copper borate by precipitation is described also in the patent application US2725857. It does not define the products and their hydration states, but gives their boron analysis.
Quote: Originally posted by bismuthate  
ok
so i took a small amount of very fine silver borate powder (about 0.2 grams) and placed it in a 100ml flask then i added three drops of HCl and imediatly, i was suprised haw fast, the brown powder turned into white powder (there was slightly more white powder) that easily floated about in the water.

And that made you exclaim: "it worked i have silver borate!:D"?

First of all, like blogfast said: This is a science forum. If you don't like the scientific method, at least do as a favour and don't share the sentiment with us. Some of us who respect and live of science, can get offended easily.
Secondly, any conclusion is only as solid as the evidence it is based upon. You got no experimental evidence, you don't even cite a reference, all you got is an indication. You don't even bother providing the experimental for the experiments you talk about, which means that even if you had any evidence, the evidence would not be evidencing anything. So behave in accordance to what you have. Describe the exact experimentals and limit the conclusions to whatever evidence you have.

And start using the Latin alphabet properly already. It's irritating!

bismuthate - 29-9-2013 at 08:46

I'm very sorry if this has offended you I planned to post a more detailed explanation later as I am currently pressed for time. I will refrain from making quick posts in the future i will probably have another post out once I have more time and make more (supposably) silver borate I will perform a more conclusive test. Please accept my apologies. Also i was unable to find the patent you mentioned. Sorry.

bismuthate - 29-9-2013 at 15:12

http://books.google.co.uk/books?id=P_MVjTFh16YC&pg=PA625...
This link that i got from Sonogasira explains the production of silver borate.
Here is my personal method that worked best for me:
You will need: 2 100ml beakers or flasks, 1g of AgNO3, 2g of borax, filter paper, filter
Steps:
Step 1: take 3g of borax. Place it in a 100ml beaker and dissolve it in 40ml of water.
Step 2: take 1.5g of silver nitrate. Put it in a 100ml beaker and dissolve it in 25ml of water.
Step 3: pour the borax into the silver nitrate.
Step 4: filter the solution.
Step 5: place the filtrand in a container of your choice. This is (indicated to be) silver borate
(I plan to verify that this is in fact silver borate this week)

AndersHoveland - 29-9-2013 at 19:51

There is this very inexplicable reaction:
http://www.sciencemadness.org/talk/viewthread.php?tid=23394

Basically, this higher oxide (I,III) of silver seems to form a soluble complex with dilute nitric acid forming a strange dark brown solution.

bismuthate - 30-9-2013 at 03:32

woah. maybe I'll do that myself. That's realy amazing. ( wiki says that it is atacked by acids but i didn't expect this).
could we mix it with other acids?

Dany - 30-9-2013 at 03:47

Yes silver manganate exist. The attached file is a crystallographic study on Ag2MnO4. Unfortunately, only the abstract is in english the rest is in german (if someone can help you with translation).

Dany.

Attachment: Crystal growth and structure of silver manganate(VI).pdf (362kB)
This file has been downloaded 503 times

bismuthate - 30-9-2013 at 03:53

as of now i cannot open the attachment, but thank you for answering my question. i will make an attempt to sythesise it with the logical route of K2MnO4+AgNO3==> 2KNO3+Ag2MnO4. (plus i get KNO3 whch is nice)

sonogashira - 30-9-2013 at 10:10

It says:
Add metallic silver to a saturated aqueous solution of AgMnO4 (room temperature) - after 10 hours crude Ag2MnO4 crystals have deposited upon the surface.

[Edited on 30-9-2013 by sonogashira]

bismuthate - 30-9-2013 at 11:18

that sounds suprisingly easy< i'll have to try it.

bismuthate - 30-9-2013 at 13:56

could you also prepare it by the way i metioned or is that impossible?

sonogashira - 1-10-2013 at 00:09

It would be easier to look it up for yourself, since you are the only one with an interest in making it! :D
Try google scholar, google books, archive.org - there are plenty of sources.