Greetings fellow nerds.
A quick video on what gloves to use with nitric acid.
I've had a lot of comments in my previous videos on nitric acid stating that i was using the wrong gloves and that i was spreading misinformation that could lead to dangerous accidents.
While those comments are not entirely wrong, as usual the science is a bit more complex.
So far i've been using nitrile gloves.
Primarily because I buy those in bulk and I try to use the cheapest gloves that still give me adequate protection.
But the problem that many commenters cite is that nitrile gloves react with nitric acid and catch fire.
The most common reference for this is the various youtube videos on this exact issue.
So am I a total moron? Well, yes I am a total moron, but not for that reason.
This is because the nitric acid I'm making in all of my videos so far is not the same nitric acid that sets nitrile gloves on fire.
I'm making dilute nitric acid or concentrated azeotropic nitric acid.
Nitric acid of these concentrations does not set nitrile gloves on fire.
Let me demonstrate.
Here i have my nitrile gloves and i'm dropping on concentrated azeotropic nitric of 70% concentration.
This is the most common concentration available for nitric acid and the concentration produced when fractionally distilling nitric acid.
As you can see, it does damage the gloves but does not set them on fire.
As usual, gloves rarely provide total protection, but instead provide resistance and time.
As soon as you spill something damaging on your gloves you're supposed to stop and change your gloves.
The chemical resistance of the gloves gives you time to do so.
Concentrated nitric acid is destroying these gloves but i would have had several good seconds to change them before they started soaking through.
And as said before, it's not catching on fire.
Let me add a little more acid and timelapse a little longer to be sure.
And there we go.
Now this is not to say it can't catch on fire, but the danger is much lower.
And the reaction is slow enough that you can still take the gloves off before it soaks through.
So I still stand by my recommendation to wear gloves when handling nitric acid.
Although i do agree with the commenters that maybe nitrile gloves in particular are not the best and there are better gloves available that give better protection.
So what are all those videos showing, they are showing the reaction of nitrile gloves with fuming nitric acid.
Fuming nitric acid is acid with very low water content, often less than 2%.
This is a very highly concentrated acid and needs special procedures to make.
You actually cannot obtain this by straight fractional distillation of a lower concentration as you'll reach the azeotrope first.
It's extremely reactive and quite dangerous, especially to nitrile gloves, let me demonstrate.
I have here another nitrile glove and now I'm going to drip on fuming nitric acid of near 100% concentration.
As you can see the reaction is much faster and i don't think i would have had enough time to put down whatever experiment i was doing and take off the gloves before it soaked through.
Let me add a bit more acid since I don't think I used enough.
And there we go, nitrile gloves and fuming nitric acid are not compatible at all.
This could be your hand if you're using fuming nitric acid with nitrile gloves.
Also even if you do manage to take the gloves off before they burn you, now you have to deal with a ticking firebomb.
Okay maybe i'm being overly dramatic but you do need to have a bucket of water or sink nearby to toss the gloves in before they ignite and lead to another lab accident.
So what if you do want to use fuming nitric acid, is there any way to protect your hands or do you have to go barehanded and hope your skill is enough?
Actually vinyl gloves are reasonably resistant to fuming nitric acid while also being inexpensive and easy to buy.
Here is a vinyl glove and i'm now dripping on fuming nitric acid.
It's hard to see on camera, but it is reacting and slowing soaking through.
So similar to nitrile gloves, it's not immune but will buy you time to take them off.
Unlike nitrile gloves though it's much more resistant and most importantly, does not catch fire.
So in future videos i'll be using vinyl gloves when i'm working with fuming nitric acid and to avoid nitrile gloves.
But for lower concentrations, both gloves will still have some protection provided you remember to take them off if there is a spill.
I hope this video was useful for you.
Thanks for watching.
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