So this video is very different then most of my videos, rather than showing how to do something, i talk about why something happens. Do you guys like the format? Is my presentation technique okay? A lot of times, expaining why something is requires a very different style and approach then showing how to do something. On a different note, this video had a funny origin: I was originally just trying to demonstrate dissolving platinum with electricity. Then during the video i answered why it worked with hydrochloric acid, but not sulfuric. Then i realized people would ask why it wouldn't work with nitric acid, and answered that. Then i anticipated that people would ask whether it would work with gold. Eventually, the whole video morphed into this long lesson about how all the acids interact in aqua regia. So i changed it from "dissolve platinum with electricity" to "How does aqua regia dissolve gold and platinum"

In Germany, even at the university level, it is still being taught that the chlorine in aqua regia is in a 'nascent state' and that's why it can dissolve gold - same thing with hydrogen and dissolving-metal reductions. It's so frustrating to be taught a theory over a hundred years out of date! Even on wikipedia the english article states it is an obsolete theory while the german article acts as though it's still totally accurate. Thank you for correctly explaining the real reason in this video.

Great video!

Babe wake up, NurdRage's dropped another video.

I used to watch these videos like every day when I was in highschool back when you were making glow sticks and Nuka cola bottles and I completely forgot about this channel but it's really good to see you're still making videos to educate people and show them how cool chemistry actually is

I am sitting in an assay lab at a palladium mine watching this video. I have samples digesting right now using aqau regia. Nice to now know how it all comes together. Great video. Cheers!

Thanks: A couple of years ago while working on my Wife's car (a used car) I found a mans gold band ring under the carpet. 'So go to the Pawn Shop; NO!' I reacted it with Aqua Regia and made a few grams of chloroauric acid, did several HCl boilings to get rid of the nitric acid and vacuum dried it. Now I have some nice canary yellow crystal. How can life be any better, Cheers, Mark PS: Keep plugging

The mechanisms are quite fascinating, ive always found it easier to remember why something is than just the fact. Understanding is the best way to learn.

One demonstration I'd like to see is gold in aqua regia compared with silver in aqua regia. Given how aqua regia attacks gold, despite it being particularly un reactive, it'd be easy to assume that it'd react with silver even more violently, but that ultimately isn't the case due to the presence of chloride. It'd be another fun demo of chemistry's rock-paper-scissors nature.

I like the -ditailed walk through the thought process of answering the question in developing steps- structure of the video, and the visual presentation of consequences of statements. I enganged in the video and learned something.

I would love to see NurdRage Collab with NileRed one day. The chemical chaos the world needs.

Would have been nice to also hear about Mercury, and it's ability to eat gold, and then be able to distil off the Mercury.

Welcome back, hope your life stabilised and you will find joy in sharing projects with us again!

3:00 "we also would be dead" that me laugh surprisinglytoo much.

Have a good New Year NurdRage. I’ve been checking out screetips, refining his old jewelry. Like your mind reader. Cheers.

Great video. You can actually use the Nernst Equation (E=E°-(RT/nF)lnQ) and a simple table of reduction potentials for the two reactions you show at 0:56 to calculate what concentrations of HCl and HNO3 are required to dissolve platinum and gold. At even somewhat dilute (less than 1M) concentrations, it becomes non-spontaneous.

Almost can’t believe I’ve been watching your videos for a decade now and there still perfect

That was actually very interesting. Always wondered why Aqua Regia could do what the individual ingredients alone could not, but apparently couldn't be bothered to get off my butt to actually look into why. And I have to admit, it is a little painful watching those precious metals being dissolved. I know it's a small matter for you to get them back. But it is still a little painful to watch, especially these days. Lol...

What a coincidence on the timing of this video! I want to electroplate a copper ring with platinum as I go about constructing a ring for my partner of 6 years. I have a few grams of platinum metal and a little aqua regia, so not enough to really experiment and figure it out myself. I thought that if I dissolve the platinum with aqua regia to make chloroplatinic acid, and then electrolyse the solution with a carbon anode and copper ring cathode, then the chloroplatinic acid should plate the copper ring with platinum. But if the aqua regia dissolves platinum it would surely dissolve the copper ring during the electrolysis... so a higher pH would probably be needed but... this is where my chemical knowledge on electroplating ends. If you NurdRage or anyone else has knowledge on this or could link me to an article (I have done quite a bit of googling to no avail) you would be awesome.

This is the best science channel on KZfaq. I'm glad to see you back again!

So happy you are not gone! Been a while since last time KZfaq recommended me a video of yours.

This format is great. I'd be completely happy to watch more like this.

The format is great and presentation is perfect!👍

We missed you. Hoping 2023 is successful for you and your channel with hopefully plenty of new videos ! Could you make a oleum video. I spent a small fortune a few months ago on oleum and would be interested in seeing you find an efficient way to make it in the lab .

Hurray! He is back! Happy new year!

Near the end I was almost sure you were going to bring up hydrofluoric acid instead of hydrobromic. I'm wondering if that would work, too, assuming the container held up.

YES. Welcome back! We missed you!

Great video. Nice to see you back. I really like this format,

Loving both formats, honestly. Thanks a lot, it's always a good day when you upload new content :)

Wow, My Curiosity, answered in thorough detail. Including some of the Alternate sources that can be used.

Hi Nurd!!! super interensting, thanks for explain the process with the reactions, your videos are one motivation for me. Happy new year from Argentina!

Holy shit so glad to see you uploading! Been subscribed since chem 101 five years ago, and now I've passed swimmingly up through pchem. Your videos have inspired me to thoroughly study the material and also to buy enough glassware that the fbi is prolly watching me 😅 many thanks for keeping this channel going and cheers to the future 🍻

Love your chemistry videos man. Please do more videos

I will drop everything to watch NileRed, Explosion and Fire, and your videos. I hope you know how grateful we all are 😊

Great to see Nurdy bouncing Chemistry around again ! Nice one. It's a Good Day when there's a new NurdRage video ;)

Just watched the cooled icecubes in liquid nitrogen. Was happy to see store still going!

ok the electricity bit was new for me so thanks

I haven't got a Nurdrage recommendation in like 4 years !

"The ultimate oxidant: Electricity!"

Nice video! I was also successfull dissolving gold using a mixture of 31% HCl and only 12% H202. Worked just as fine, just had to be heated a lot.

Happy to follow you for more than 10 years 😃

"We would also be dead" I absolutely lost it

You hit the nail on the head with this - to dissolve a noble metal, you need an oxidizer and a complexing agent. Interestingly acidic conditions aren't required - the most common leaching solution in gold mining is a slightly alkaline solution of cyanide (strong complexing agent) with atmospheric oxygen bubbled in as the oxidant, dissolving the gold to form gold(I) cyanide. To reduce the toxicity for home experiments, thiosulfate or thiourea can also be used in place of cyanide. These are all much slower than aqua regia, but it works given enough patience.

Haven't been notified of your uploads unfortunately even though I'm subbed and got the bell on. Good to see you're still around!

Nurdrage uploaded, it truly is a happy new year

Wait, when did NerdRage come back!

Hadn't really thought about it before, but it makes sense that complexation would play a big role in driving the reaction forward. This makes me wonder if it would be possible to dissolve noble metals using electricity in solutions of strong chelating agents, like EDTA or DOTA. Crown Thioethers might be even better, heavy metals tend to really like binding to sulfur.

Welcome back again I really enjoy the yearly visits from you

So glad you are back!!!!

I've been wondering this since I read about aqua regia in a set of encyclopedias we had as a kid, Compton's. Thank you!

God, stop the world from spinning for a sec... NurdRage just uploaded and I need to focus.

KZfaq changed forever the day we first heard "Greetings, fellow nurds"

Back to your best I feel, have a great new year.

Well welcome back!! Long time no see!!!

I audibly gasped when you chucked a 1oz bar of platinum into beaker. Just more than $1000 getting chemically dissolved, no biggie.

The fact the products of the reaction are more stable than the reactants does not imply the reaction will occur if the activation energy is high. That's the difference between thermodynamic and kinetic control of the reaction.

I used to use Hexachloroplatinic acid hexahydrate to make the catalyst for curing silicon polymers via vinyl-hydride bonds, so this video was extra interesting. There'd be about $250,000 (in 1990's dollars) swirling around in pot when I made that stuff, so I would brood over the reaction like a hen on her eggs. The unreacted chemical was orange and would clump into jelly-belly sized and shaped lumps. If I didn't know any better, I'd try to eat one.

Beautiful explanation.

the goat is finally back

CodysLab made a great explanation of this in Minecraft.

OMG...he's back!!!!!!

Awesome very thorough and much appreciated!!😇

Great to see you! Hope you have a Happy & Healthy New Year !

H2O2 is a common substitute for HNO3 in gold refining

Really appreciate the effort and detail. Great video.

One oxidizes the other is able to dissolve the oxide, right?

Your uploads may be rare, but I still get excited to see them in my feed. Quality over quantity.

Very good explanation. I hope you do more like this. Also, speaking of chlorates and the promised part 2: I read, that industrially, they bubble Cl2 through hot Hydroxide, making ClO- which disproportionates into ClO3-. Could a divided setup like this enable the more efficient reaction without PH control? Could it also allow for less demanding electrolysis conditions or skipping the electrolysis outright in favor of pool chemicals?

Now @Cody'sLab is going to extract the trace platinum from 5lbs of commercially produced chlorate.

Yo, you made me think of a couple interesting questions: if we were on a planet with a chlorine atmosphere what metals would be precious there? Would anything not precious here suddenly become precious there?

Thank you. Happy new year.

So, shouldn't in theory oxygen gas bubbled in a concentrated hydrochloric acid solution be a good oxidising agent for the dissolution of gold/platinum ?

Loving the new format!

Is there a way to dissolve other Platinum group metals - for example Iridium or Ruthenium?

Another nerd rage video fuck yeah. Good to see you back bro hope you're doing all right.

YES! THE MAN THE MYTH THE LEGEND IS BACK!

Holy shit, the man lives yet!!

01:07 I'd disagree - a gold panner claimed on his video that HCL will dissolve gold but it'll take some time. Imo oxygen is a catalyst that helps speed up the rate of dissolution/decomposition. HCl will dissolve gold on its own but it will take time that you won't give to it. It's clear the chlorine is required to dissolve gold. They even use chlorine to clean the gold bars during their manufacture.

Hydrofluoric acid dissolves gold and platinum too, maybe it's related to the halogen group? Would be interesting to see an experiment with hydrobromic and maybe even hydroiodic acid

I had this doubt too.

Thanks for uploading this video after pondering on it. :)

Would you be interested in showing fractional destillatiom of wood and plastic tar ?

It's funny, people see gold as some precious metal that must absolutely cost lots of money, but the rest of us see it as a yellow metal that is useful for so many things rather than just wearing it... :P

ec 30 2022 a very welcome vid' for diving into how and why of the reactions that occur at the molecular level. this understanding is in line with what i am trying to learn w/ NP and RP chromatography. this vid' will be re-viewed many more times. as an aside , ... at Boeing , plant 2 , south of Seattle my long ago job had me take samples of a gold-plating solution for PCB's. when the advisor showed me what to do he mentioned in passing not to breathe the visible gray fumes that arose on adding a base reagent to the solution. somehow i remembered that gold is soluble in a cyanide solution. once it ppt'd and dried it was weighed. and with this data the plating solution gold conc' could be determined. now i live in colorado and just 22 miles north via a 'gold - belt' road is Cripple Creek where modern methods using a spray of cyanide solution is in use to recover the gold missed out by methods used in the 1890's the original assay lab / office is still there on display to visit and fathom the lab work it took to get an answer.

I have seen some people here in india using sodium chloride and Nitric acid mix with some amount of H2SO4 to form complex I think here the NaCl act as Chloride source and the mix is able to form complexes ! Can you go or we go with exact process ?

SUPER GOOD. Great topic, interesting, obvious question that goes unask.

What would be the reaction, if any, with 100% liquid chlorine (pressurized) and gold or platinum?

This was a great video, thanks for the information and examples.

I always thought there was an equilibrium reaction between Au + HNO3 and Au(NO3)3 that strongly favoured Au and that HCl drove the reaction towards completion by reacting with Au(NO3)3 to form AuCl3 that was complexed away as HAuCl4

Maybe perchloric acid would work? It is an acid with oxidising properties, after all.

Does H2O2 work as an oxidizing agent? Or HF as a complexing agent?

"If we lived on a world with a chlorine atmosphere..." "...we'd be dead." A bit of a catch-22.

Casually dissolves $1000 of Platinum

Would love to see I/I2 action on platinum

NurdRage please do a video on rhodium salts converted into rhodium metal……..🙏

Try it with hydrofluoric acid and nitric acid. Wonder if it would be more or less vigorous.

Glad to see you’re okay!

For a sec I thought this was sreetips but it's only nurdrage

yes the boss is back!!

Damn I love this Chanel!