Stannous Chloride Crystals.

[Slayer-PGM]

Hey guys can you please confirm Stannous chloride?
I am getting white crystals of Stannous chloride here. Will this work good? I know we have to mix pure tin powder in to HCL but what is this white colour crystals of Stannous chloride?

http://www.abenterpriseindia.com/drug-intermediate.html#stannous-chloride

Now the reason I am confused is that Steve gave this recipe for Stannous chloride and he didn't mentioned the crystals at all and according to him only Tin and HCL is needed to make the Stannous chloride so what do the guys above selling which is white powder crystals??

1) 2 grams of pure powdered tin
2) 30 mL 32% HCl
3) Heat until fizzing begins (this takes around 10 seconds depending on your heat source)
4) Stop heating and let react uncovered until the solution clears, the solution should be colorless.

Thanks.

 

[FrugalRefiner]

Slayer-PGM,

When you dissolve tin metal in hydrochloric acid, you create stannous chloride solution. If you were to evaporate off all the liquid, you would end up with stannous chloride crystals. These crystals can be redissolved to form stannous chloride testing solution.

If you download the book in my signature line, you'll find a description of making the testing solution from the same stannous chloride crystals.

Dave

 

[Slayer-PGM]

Slayer-PGM,

When you dissolve tin metal in hydrochloric acid, you create stannous chloride solution. If you were to evaporate off all the liquid, you would end up with stannous chloride crystals. These crystals can be redissolved to form stannous chloride testing solution.

If you download the book in my signature line, you'll find a description of making the testing solution from the same stannous chloride crystals.

Dave

Thank you for the reply. After reading the book I am more confused now. As per Hoke she said to use Stannous chloride crystals, TIn powder (both ) in HCL and even diluted HCL but Steve said to use only pure TIn powder and HCL to create the SC solution. As per my understanding :
I can just buy pure tin from a shop and add it in HCL and heat till it form colorless solution. This is perhaps the best and easy way to create the solution and cheap too.
What exactly to do with Stannous chloride crystals? Whats the use of buying the crystals if one has to mix it with Tin and HCL. Why not just use pure Tin and HCL in the first place?

Thanks

 

[maynman1751]

You can also use 95/5 solder (95%tin 5%antimony) dissolved in HCl. Search the forum. You'll find your answers.

 

[Slayer-PGM]

You can also use 95/5 solder (95%tin 5%antimony) dissolved in HCl. Search the forum. You'll find your answers.

Please don't confuse me more. The more I search the most complicated it is. I am getting pure Tin in my area so can I just add in HCL and heat it? I also have Stannous chloride crystals (White) with me now. Can I use that instead of Tin in to hcl and heat it??

I read the book and saw Steve tutorial too. I did my research and please tell now which method would I use?
Thanks

 

[butcher]

What you are trying to make is a tin salt solution (tin metal dissolved in solution), called stannous chloride.
The tin in solution you want is SnCl2, this stannous chloride is what we used to test for gold, it will reduce gold in solution giving gold ions electrons, which reduces (gain of electrons)the gold, While the stannous is oxidized (loss of electrons) in the reaction, forming a purple solution of colloidal gold, small clumps of elemental gold in solution which reflect light giving the solution a purple color called purple of Cassius.

The stannous chloride can be made with a salt (crystal) (or powder) of tin chloride, or can be made from elemental tin, with tin metal dissolved In HCl, or with the tin powder (or crystal) dissolved in water with a little HCl to keep the solution acidic.

the stannous chloride SnCl2 can change into other forms of tin salts in solution, which will not test for gold, this normally happens with the stannous chloride solution SnCl2 when stored.

In water SnCl2 hydrolysis can occur forming an hydroxide tin salt:
SnCl2 + H2O <--> Sn(OH)Cl (s) + HCl
Free HCl can help to keep this reaction to the left, keeping your stannous chloride in solution from forming this hydroxide.

Stannous chloride SnCl2 in solution can also oxidize from air or oxygen forming stannic (tin) salts SnCl4 (stannic chloride):
6SnCl2 + O2 + H2O --> 2SnCl4 (aq) + 4Sn(OH)Cl (s)
Keeping the solution acidic with a little free HCl in solution and some elemental tin metal, we can keep the stannous chloride solution SnCl2 fresh longer and working to detect gold.
Stannic chloride with tin metal:
SnCl4 + Sn -->2SnCl2 (aq)

We can go on with this but basically, when you make stannous chloride, whether made from tin salts (powders) (crystals), or with elemental tin, adding a little extra HCl and tin metal will keep your stannous chloride fresh longer, and working to detect gold in solution, keeping the stannous chloride SnCl2 from forming one of the other tin salts in solution, like stannic or hydroxide...

I make my SnCl2 with tin metal, I use tin solder about 95% tin with 5% silver or antimony, ( I smash the tin solder wire metal flat, and shave off some slivers of tin with a pocket knife add a little HCl and heat to dissolve the solder,to make the SnCl2 clear solution, I put this in the small testing dropper bottle, add bit of HCl and small piece of tin to the bottle, to keep the stannous chloride fresh, (I also keep it stored out of light for good measure),I also try to fill this bottle with solution to keep air volume down, I do not make much at a time.

SnCl2 solution goes bad eventually, it does not have a long shelf life, free HCl and tin can make it last longer, with this in mind you really do not want to make it and store it, if you do not use it often you can just make it fresh each time you need it, if you do store it having a solution of gold standard (gold in solution) to test to see if your stannous chloride is still good is needed.

 

[jimdoc]

Having a known gold solution to test your stannous is very important.

Jim

 

[rickbb]

I read the book and saw Steve tutorial too. I did my research and please tell now which method would I use?
Thanks

Either one, they both will provide you with the test solution you need. Use which ever one that is more convenient for you.

And as Jim said, having a solution that is know to carry gold to test your SnCL2 against is also important.

 

[arsenic123]

Great post guys.
As far as I understand one can buy pure tin powder and dissolve in hcl with a little heat. That is one way.

Secondly one can use crystals also to dissolve in water with a little hcl to make SC.

Thank you

 

[butcher]

Bingo, adding HCl and tin will make either last a bit longer, keeping the SnCl2 fresh for a longer time.

 

[MarcoP]

I've finally find, online, some SN99,3/CU0,7 solder, in my area when I ask for lead free material they all think I'm nut :evil:

Thanks a lot for explaining all different methods in making SnCl2!

 

[Claudie]

A long time ago, I bought something like this: http://www.ebay.com/itm/1-LB-TIN-POWDER-99-9-PURITY-325-MESH-/191178314446?pt=LH_DefaultDomain_0&hash=item2c831d92ce

It is what I still use to make Stannous Chloride. 1Lb will probably be enough to last 50 years or so. :|

 

[MarcoP]

For 100gr of tin metal powder they ask about €11 but for 250gr of 99.3% tin solder its only €15 http://m.ebay.it/itm/281045691353 it took a while but I found it 8)

 

[g_axelsson]

I bought a beated up pewter bowl in a second hand store for about 80 cents. (5 Swedish krona) It will last me a lifetime, I'm just cutting a piece of it whenever my old stannous have gone bad. The pewter is made up of 97% Sn and 3% Sb, works just fine.

Is there any contamination that would make stannous chloride not working? I mean, we are testing dirty solutions of mixed base metals and gold so there are already a lot of contamination in the mix already. If some comes from the stannous it shouldn't matter too much.

Göran

 

[MarcoP]

I'm finally making mine! 1gr Sn + 30ml HCl + 90°C heat till all Sn is dissolved. After taking the picture I've noticed the solution going down to 25ml so I topped it up and covered with a plastic lid. I believe I will need a watch glass, an Erlenmeyer or boiling flaks for the job.

Yes Göran, I believed that from the beginning. Thanks for confirming it!

 

[MarcoP]

Uhmm I ended up with crystals in solution.

I've used 1gr of hammered and sliced Tin solder as described above, 30ml of HCl which went down to 25ml and I had to add another 5ml to make it up, heated to 90°C till all tin was dissolved.

I've storing it in a 30ml dropping bottle to keep most air out of it, added a bit of Tin solder and few drops of HCl ready for storage.

Did these crystals formed because I added too much heat thus evaporating the solution and reducing some Stannous Chloride solution to its salts? Seems easy but the smallest change in chemistry can make a lot of difference.

edit: or does it needs a little water to dilute the slightly concentrated HCl?

 

[butcher]

You may need a little more free HCl may help to dissolve the tin stannous salts, and keep them dissolved, and to help keep the solution fresh, keeping a little bit of free metal in solution will also help to keep it fresh.

When I make stannous chloride I do not heat it to evaporate the solution that much, just enough to help speed the reaction somewhat, I do not see that you have done would do much harm with your heating it the way you did, (and may even be beneficial), as most of what evaporated was mostly water involved in your original HCl acid, when cooling you did have less solution to keep the tin dissolved in solution, which most likely did form the stannous salts, adding some more HCl should put these back into solution, you do not want to add, or have excess water in solution, as the stannous chloride can hydrolyze or form a tin hydroxide with more water involved.

Now if you add to this thread with more posts and pictures of making you making your gold standard (test solution), to test your newly made stannous chloride with, and showing the results of those tests, you will be helping others to learn from your experiments, giving them more to go on by seeing your work, good start for an educational thread, not only for you but also for others trying to learn with you...

Good job keep up the good work.

 

[GotTheBug]

I make mine in a small dropper bottle, brown plastic from the pharmacy to be exact, and keep a few pieces of solder in the bottom for freshness. Hasn't failed me so far, and I find having 50 mL is more than enough for me.

 

[joekbit]

I'm a noob at all of this. Spent about the last 2 months researching, watching vids, reading massive amounts of wiki chemical info and experimenting with a few random scraps, As to the subject at hand. I found a post about stannous chloride and how to make it and I tried it. Same method as mentioned here. With one exception, I don't heat it. and its' always crystal clear with no crystalline development in the bottom and it seems to be doing the job perfect.

I have some AnCl / I think that's correct for gold chloride. I created it using a 22k gold stamp so I knew I had no impurities. The result was as advertised, immediate reaction, purplish color then as black as coal in just a few seconds.

With that being said, quit heating it, and I bet you never see another crystal in the bottom. Just let it sit at ambient /room temp until the tin is dissolved and the bubbles stop. and like the last post said I add a bit of tin and a few drops of HCI now and then just to freshen it up.

 

[Shark]

I only heat mine to hot coffee temperature just long enough to see the reaction going pretty good. I then take it off the heat and let it work on it's own. You don't have to boil it or even heat it for any length of time. I have found running hot tap water on the side of the glass to be enough to get it going pretty quickly also. If your going to use tap water to heat it, install an outside hot water line, don't do it in the house.