Warning: Acids are corrosive, wear gloves when handling them.
Greetings fellow nerds.
One of my viewers donated this 2.5g bar of palladium metal.
This is an extremely generous gift, as the spot price of palladium today is even higher than that of gold.
I would never have bought this myself.
But thanks to this donation we can do some palladium chemistry.
In this video i'm going to test its chemical resistance against a few common known corrosive substances
and see how we can efficiently convert palladium metal into a metal compound.
Let me cut it out of the packaging.
And there we go, one 2.5g bar of palladium metal.
On the backside we have the pamp suisse "Lady Fortuna" design".
Let's see what chemicals we can use against it.
But first we should weigh it.
This is a pretty small piece so it will be hard to judge how deeply it's getting damaged.
If we know the mass beforehand we can see how much it changes and we can notice even small amounts of damage that are invisible to the naked eye.
Looks like we have about 2512 milligrams.
First I'm going to use the classic hydrochloric acid at 30% concentration.
And i'm also going to compare it to aluminum foil, a very reactive metal.
As you can see it really goes on the aluminum but the palladium looks immune, at least at these temperatures.
I left it there for another hour before taking it out, washing it and drying it off.
And here we are checking the mass, no change.
So if hydrochloric acid is doing anything it's imperceptibly small.
Next let's try bleach at 7% concentration.
I know this seems a little weird but i decided to add this test after my experiences with ruthenium metal.
We showed before that ruthenium had the strange property that it was nearly invulnerable to most corrosive substances.
It was even immune to aqua regia.
But amazingly it was defeated by bleach.
However palladium seems to be perfectly normal and even after an hour of soaking I saw no change in mass.
Even though it reads as lower by 1mg, that's within the error of the balance.
I've known this balance to have up to 3 mg of error on repeated measurements.
Anyway, moving on let's try hydrogen peroxide and sulfuric acid.
And I'm going to also compare it with copper metal.
Right now we have 3% hydrogen peroxide and I'm now going to add in sulfuric acid.
We get a very strongly oxidizing acidic solution.
It's not piranha solution exactly since we have more peroxide than sulfuric acid, but it should still do some damage to metal if the metal can be damaged at all.
As you can see it's reactive enough to dissolve copper which normally doesn't dissolve in sulfuric acid .
I left it in for an hour before pulling it out.
And this time we're getting something.
We can see some damage to the surface as the solution attacked the palladium.
It's not very much though, but it's there.
I checked the mass and it didn't change.
So maybe we didn't really dissolve the metal but just oxidized the surface.
I'm still thinking of the implications, but maybe this is good to know and might be applied to cleaning or reactivating dirty palladium catalysts.
So now let's try nitric acid.
I'm adding in concentrated 67% nitric acid that I made myself.
From what i read it should react but i'm not sure how fast.
And wow that is actually a lot faster than i expected.
I thought it would be slow being a precious metal and while it is much slower than base metals like copper this is still very quick.
It's only been a few minutes and i'm clearly seeing the metal dissolving and the features getting destroyed.
What's happening is the palladium metal is reacting with nitric acid to produce palladium nitrate and nitrogen dioxide gases.
You know what, I actually don't want this completely dissolved since i have a few more plans for the solid metal
so i'm going to stop it now and take it out at just 5 minutes.
And here it is after I dumped it out and washed it with water.
It's definitely dissolved quite a bit.
The features are still present but have suffered a lot of damage.
I was going to test aqua regia but if nitric acid alone can dissolve it this quickly there is no point.
And here is the mass, clearly we're well beyond the error of the scale and have certainly dissolved 112mg of mass in just five minutes.
This is an interesting contrast to platinum which took days of boiling hot aqua regia to dissolve.
But palladium looks like it can dissolve in nitric acid at room temperature at much faster rates.
Perhaps this property can be used to separate the two metals.
I'm not sure, perhaps the precious metal refiners can chime in.
Anyway I plan to do a few more experiments with this piece of palladium and make more compounds, so i'm going to set this aside.
And meanwhile over here I now have 112mg of palladium metal dissolved in 10ml of nitric acid.
Palladium nitrate is an interesting chemical in itself and i'll probably evaporate this down and crystalize it for use.
Palladium is a tremendously useful catalyst in chemistry and I'll see if I can explore some of that in future videos.
Right off the top of my head I want to try hydrogenations with it.
Maybe even hydrogenate alkenes, or make hydrogen peroxide in a future mega project.
Anyway, so that's the chemical resistance of palladium metal.
Thanks for watching.
And thanks again to my viewer who donated this valuable gift.