Fred - Test Tube Tests:

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duke1025

Member
Joined
Aug 27, 2020
Messages
19
So i am getting ready to do the tests....

Acquaintance Tests:

Test Tube Tests:

1) weight of metal
2) amount of acid ml
3) heat temperature applied
4) reaction - speed of reaction
5) reaction - total time of experiment
6) color during reaction
7) color of fluid completed reaction


Metal + Acid =
------------
1) Copper & acid -

2) Brass & acid -

3) Bronze & acid -

4) Nickel & acid -

5) Zinc & acid -

6) Tin & acid -

7) Lead & acid -

8) Iron & acid -

9) Bismuth & acid -

10) Titanium & acid -

11) Gold & acid -

12) Silver & acid -

and finally in the end, i will make an AR solution and test each metal as well.

platinum group metals, such as rhodium, palladium, ruthenium, osmium, and iridium etc not included in tests, do not have available for testing.

ACIDS to be test against: Hydrochloric, Sulfuric, Nitric, Caustic Soda (Lye), Salt (sodium Chloride)

What would you add to these tests?
Thanks!

Basic setup: immersion heater, test tube holders, 90 deg inverted clamps, 1/4" threaded rod 14" long, AC lamp dimmer to control heater & a test tube.
 

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As you learn more you will come up with more of these to try, you can do these types of small experiments to gain a better understanding of the materials you are working with, with most any metals or processes we use, I often make up my own experiments to learn more of these reactions, or even do some small experiment with different types of scrap to find a good recovery method...




Take notes of how a metal like tin may dissolve in HCl as stannous chloride, and when diluted can hydrolyze to stannic chloride making filtering a nightmare.

Note, how when you have lead and silver chlorides in a solution you can separate the lead salts from the silver salts with boiling water, how it takes the fluffy silver chloride a while to settle in the solution of dissolved lead...

Note how with iron you can have several different oxidations states and can give the solution a wide range of colors depending on the oxidation state, solution can range from yellow to green or red-ish to brown-black.

Some iron oxides are not attacked very well by aqua regia while other iron oxides would easily go into solution with any gold...

Use copper to cement silver from solution, (just because like watching it so much).

Make up some stannous chloride, do some experiments testing for gold or PGM in solution, try solutions with varying gold content, diluted and concentrated.
Make up some (copperas) ferrous sulfate crystals (iron and 10% H2SO4) test for gold in solution, or use to precipitate gold from the solution...

Experiment to see how free nitric affects the testing of gold in solution.
Make up some gold solution to test your stannous chloride.


Some metal salts hydrolyze when the solution is diluted (for example tin chloride).

Some acids will not attack or dissolve a metal very well if the acid is concentrated, but can easily dissolve it in a more dilute solution.
Note silver in concentrated nitric versus dilute nitric...

Make up some silver test solution, and try it out.

Look up and do some silver one-pot reactions, and copper one-pot reactions taking these metals in and out of solution using several different reactions in one pot.


Note the reactivity series of metals, how metals may react with water, or acid or are unreactive to acids, and how metals can react with carbon and heat in relation to the reactivity of these metals ...
Do some experiments from what you learn.

Note how some metals are amphoteric they can be precipitated by a base solution and then redissolve if more base or caustic solution is added...

Note how traces of copper in solution react to an ammonium hydroxide solution.

Make up some CuCl2 add a copper note the green goes dark brown to black as the solution begins to be saturated as the CuCl2 converts to CuCl concentrate the solution till it saturates and CuCl begins to precipitate as a white powder in the blackish solution, add a few drops of HCl and bubble in some air to convert it back to dissolves CuCl2 a nice green solution ready to dissolve more copper and other base metals.

Try the above experiments with an iron chloride making ferrous and ferric chloride to dissolve copper and other base metals, note how it can also hydrolyze...

Try dissolving gold in different solutions, HCl & nitric, HCl & 30% H2O2, HCl sodium hypochlorite (bleach), HCl MNO2... incorporate these in your testing experiments, Now try a few experiments using reagents to precipitate the gold...

See how metals like aluminum hydrolyze and consume acids by displacing the hydrogen, how it makes a goop hard to filter.

Test for iron in solution Hokes pg. 100

There is no limit to what we can learn from these small test-tube experiments, No limit on what we can try, you use your imagination, you can try these types of small experiments to gain a better understanding of most anything your studying or working on in a recovery or refining process, the recovery methods, gaining a base for troubleshooting problems, even determining if you may encounter problems with different materials or types of scrap, improve your testing skills...
 
Regard your basic setup, I would make a rolled tube of 1" or 2" Kaowool (fiber blanket) and slip it over your heating element.

It would help to retain heat and would be slightly less traumatic if you accidentally bumped into it.

Peace and health,
James
 
Butcher, AWESOME! Thank you, i will try these experiments also, added to list.
I will post my results to the board with some pictures as do it. Thanks!

Cosmetal: thanks for the suggestion... will do.. sounds like a good idea as wind also moves around and can cause a variance in temperature around the tube, stabilize it... Thanks!
 
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