Tip to prolong stannous life.

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heliman4141

Well-known member
Joined
Aug 10, 2013
Messages
180
This tip is for new members & members that don't normally mix their own Gold test solution regularly.
When you purchase the small stannous test squeeze bottle what you want to do is do your Gold test, then very very gently squeeze every last bit of air from the bottle, then place the cap back on while holding it squeezed. This way no contamination from the air gets to your solution.
Normally one is lucky IF under normal use a bottle remains in good quality more then say 2 weeks or so. My solution has just been tested against a known Gold bearing solution & is still working good as new & its 7 weeks old now, yes, the squeeze bottle is almost collapsed but I didn't have to mess with mixing any which is nice & the tin in the bottle still looks like new no breakdown at all.

Ill probably mix my own batch in another 2 weeks & just use the tin that is already in the bottle, another nice thing about it.

Anyway, this will give anyone a LOT more milage timewise on the stannous.

Dave
 
We just keep 4N tin powder in the bottom of the vial--the tin keeps any stannate reduced to stannous.

Lou
 
I mixed up a small batch of stannous using 25 ml HCl, 75 ml distilled H2O, several beads of pure tin (bought on eBay), and 1/8 teaspoon stannous chloride anhydrous (also bought on eBay). Every time I take it out of the refrigerator for use, I test it against a 1% gold chloride test solution (also bought on eBay). It has never failed me in over 2 years of use. I would be lost without it. However, I still have enough left of all the ingredients to last me a lifetime. So if you see me out there, and I'm lost, it's because of something other than running out of stannous chloride test solution.
 
Thanks for the feed back fells,
I had 2 bottles go bad on me in the past 2 yrs. and had considered from what id read here in the past about it going bad from contamination with the air. My area has high industry & I thought it was that or perhaps I was buying old stock maybe? I always kept it in my cool dry basement away from light, what do you guys think happened to my first 2 bottles? The tin in them completly broke down to a mushy powder looking goop & when tested to a known gold solution it tested as free of gold. Only thing ive changed that seems to have fixed the issue is my keeping any air from entering my bottle now. Im reading pros & cons about its life from both camps, frustrating.

Dave
 
Given that 5 people have effectively said exactly the same thing I'm sure you don't need to continue feeling frustrated Dave?

Jon
 
heliman4141 said:
Thanks for the feed back fells,
I had 2 bottles go bad on me in the past 2 yrs. and had considered from what id read here in the past about it going bad from contamination with the air. My area has high industry & I thought it was that or perhaps I was buying old stock maybe? I always kept it in my cool dry basement away from light, what do you guys think happened to my first 2 bottles? The tin in them completly broke down to a mushy powder looking goop & when tested to a known gold solution it tested as free of gold. Only thing ive changed that seems to have fixed the issue is my keeping any air from entering my bottle now. Im reading pros & cons about its life from both camps, frustrating.

Dave

Keeping the air out is the answer.
 
Yes, the addition of the tin has that effect. Chemically it's producing Hydrogen gas as the by product of the reaction if my limited chemical knowledge serves me correctly?
 
That is correct. Adding a small bit of tin to stannous chloride will produce hydrogen gas as part of the reaction, thus displacing some of the air in the container. Heliman's method works also, to help keep stannous fresh, but not as a long term solution. Tin powder is relatively cheap.
 
It's not the gas displacing the oxygen, it's that any oxygen that gets in and makes stannate attacks the tin and gives you stannous.
 
Thank you for the correction. I have made the correction to my notebook. I appreciate it, Lou.
 
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