Stannous Chloride Container

[boylejob]

This is probably a stupid question but I am going to ask it any way. I am wanting to test circuit board traces for gold plating so based on what I have read on this site I need a stannous chloride solution. If I am reading everything correctly I need to dissolve 2 grams of tin in 30 ml of HCl. My question is what kind of container do you keep this solution in?

My understanding of the testing procedure is to place a drop of HCl and a drop of bleach on the trace to be tested. After allowing to set for awhile, soak those two drops up with a q-tip. Then place a drop of the stannous chloride solution on the q-tip and observe the color. Can the solutions be kept in a glass dropper bottle with a glass dropper?

I have a great respect for chemicals, but I am a far cry from being a chemist so I want to insure I am keeping these chemicals in the proper container.

Thanks!

 

[jeneje]

Can the solutions be kept in a glass dropper bottle with a glass dropper?

Yes
Ken

 

[niteliteone]

If you are talking about a glass dropper bottle with a rubber bulb, it will work for a while, before the rubber is deteriorated and cracks.
Once that bulb cracks air gets inside the bottle and basically ruins the solution.
I solved the problem by using small 30 ml reagent bottles with a ground glass lid as in the picture.
I dip a q-tip in my gold solution then with my stir rod I get a drop of stannous solution and apply it to the q-tip or spot plate, which ever I am using at the time

 

[bmgold2]

That's a real nice bottle niteliteone. I use a very simple plastic 1 ounce bottle to store my stannous chloride. I make it right in the bottle and just leave the undissolved tin solder in the bottom. I use a plastic pipette to get a drop or two out when I do my tests.



You can see I need to make up some more but there is still several tests worth of solution in the bottle and it is still working. I only make up maybe a quarter ounce or less at a time since I don't use a lot of it and so far I have run out before it went bad.

I do like that little ground glass bottle though.

I never heard of that test for gold but it sounds like it should work. If I ever run across some parts that I'm not sure of I'll try it.

 

[pgms4me]

I found mine lasts 3 times as long if I keep it in a small dark brown bottle and away from light..

 

[Harold_V]

This is probably a stupid question but I am going to ask it any way. I am wanting to test circuit board traces for gold plating so based on what I have read on this site I need a stannous chloride solution. If I am reading everything correctly I need to dissolve 2 grams of tin in 30 ml of HCl. My question is what kind of container do you keep this solution in?

My understanding of the testing procedure is to place a drop of HCl and a drop of bleach on the trace to be tested. After allowing to set for awhile, soak those two drops up with a q-tip. Then place a drop of the stannous chloride solution on the q-tip and observe the color. Can the solutions be kept in a glass dropper bottle with a glass dropper?

I have a great respect for chemicals, but I am a far cry from being a chemist so I want to insure I am keeping these chemicals in the proper container.

Thanks!

It might interest you to know that this test is fraught with problems. If you do happen to dissolve gold, the very fact that it is plated over base metal (copper) which would remain, the gold you dissolved would most likely be cemented as the level of acid fell, so the test most likely would not be conclusive. You may or may not still have traces of gold in solution, so unless you got a purple reaction, you wouldn't really know if you had gold, or not. Personally, I wouldn't trust it to make determinations.

By sharp contrast, a drop of nitric acid placed on a trace would readily determine of gold was present, as it would remain gold colored, even if you managed to dissolve all of the base metal beneath the test are. With this test, you do risk having the gold break up to tiny fragments if it's not very thick.

Harold