Sciencemadness Discussion Board - H2SO4/ HNO3 mix on my hand

H2SO4/ HNO3 mix on my hand

Tensai - 30-4-2015 at 04:06

Hello,
How are you doing, chemists?

Actually, I got into an accident 4 days ago in Organic Lab while mixing H2SO4 and HNO3, the accident happened when I took out the thermometer and touched it with my two fingers while still having the mixture in it,
The tempreture was about 10-20 celsius
There is a still yellow scar around my finger and I am afraid it won't vanish that easily. I asked my lab instructor, and he told me that it is okay and it will go away soon. But I am still worried-.

Screenshot_2015-04-30-15-05-48.png - 2.8MB

Chemosynthesis - 30-4-2015 at 04:34

The yellow color will fade and I doubt you will have a permanent scar. I've seen way worse end up perfectly fine.

NedsHead - 30-4-2015 at 05:18

I'm new to chemistry as a hobby and have already stained my hands more times than I care to admit;) WFNA, RFNA and just last week silver nitrate solution.

Don't worry it will fade away soon

annaandherdad - 30-4-2015 at 08:50

The yellow stain is caused by the nitric acid. As everyone says, don't worry, it will go away.

Of the 3 common mineral acids, the order in which to worry about skin contact, from least to most worry, is HCL -> HNO3 -> H2SO4, and HF is off scale. In any case, if you get some on you, wash it off immediately. And don't under any circumstances get any of these in your eyes.

DraconicAcid - 30-4-2015 at 09:44

The yellow stuff will peel off in a few days. If you're the kind of person who enjoys peeling sunburns, you'll have fun with it.

Loptr - 30-4-2015 at 10:27

The other day I showed my wife what anhydrous nitric acid will do to a nitrile glove.

Needless to say she is now even more terrified.

On another note, McMaster has very cheap Viton o-rings for when you have to replace the thermometer adapter o-ring.

[Edited on 30-4-2015 by Loptr]

macckone - 30-4-2015 at 10:53

Very useful loptr. I think I will order some.

PHILOU Zrealone - 30-4-2015 at 11:25

The yellow comes from tiny amount formation of picric acid from amino acid tryptophan.

DraconicAcid - 30-4-2015 at 11:41

Quote: Originally posted by PHILOU Zrealone

The yellow comes from tiny amount formation of picric acid from amino acid tryptophan.

I find that hard to believe. A lot of nitrated things are yellow, not just picric acid.

Loptr - 30-4-2015 at 11:43

Quote: Originally posted by macckone

Very useful loptr. I think I will order some.

Make sure you get the cheap ones, since they do sell some expensive ones. I received 100 for probably about $7 total.

[Edited on 30-4-2015 by Loptr]

[Edited on 30-4-2015 by Loptr]

PHILOU Zrealone - 1-5-2015 at 02:37

Quote: Originally posted by DraconicAcid

Quote: Originally posted by PHILOU Zrealone

The yellow comes from tiny amount formation of picric acid from amino acid tryptophan.

I find that hard to believe. A lot of nitrated things are yellow, not just picric acid.

It is called xanthoproteic reaction and forms xanthoproteic acid upon reaction of aromatic ring containing amino-acids in proteins...like tryptophan, tyrosin, phenylalanine. The easiest nitrated one is tyrosin.

The yellow colour turns orange in basic media what is very common with dinitrophenol and trinitrophenol related compounds.

tahallium - 27-4-2020 at 20:54

I spilled sodium chromate solution (bleach and chromium hydroxide method) on my hand two day ago I washed my hands immediately and I don't know what should I do

B(a)P - 28-4-2020 at 02:21

Quote: Originally posted by tahallium

I spilled sodium chromate solution (bleach and chromium hydroxide method) on my hand two day ago I washed my hands immediately and I don't know what should I do

How much did you get on you? Dermal contact with chromate while not ideal is the least concerning exposure pathway. It can lead to dermatitis and sensitisation after reaped exposure. Do you have any irritation on the stop where you were exposed? Exposure for longer durations or to larger amounts can lead to ulceration. Ingestion or inhalation has far worse consequences. Did you cary this out in a well ventilated area? I imagine you had some Cl to deal with, but I don't know how fast this reaction would proceed..... Probably best to review your choice of PPE before trying this one again.

Fery - 28-4-2020 at 11:46

Tensai - it will disappear. Decades ago I used conc. HNO3 to get rid of skin warts, very efficient, though I do not suggest this method to others (risk of exposing for too long).

mackolol - 29-4-2020 at 03:28

Quote: Originally posted by Fery

Tensai - it will disappear. Decades ago I used conc. HNO3 to get rid of skin warts, very efficient, though I do not suggest this method to others (risk of exposing for too long).

Oh man... ;D how did it go? Sometime ago I thought should I try conc. NaOH on my wart but left this idea.

Bedlasky - 29-4-2020 at 04:55

Quote: Originally posted by Fery

Tensai - it will disappear. Decades ago I used conc. HNO3 to get rid of skin warts, very efficient, though I do not suggest this method to others (risk of exposing for too long).

Laboratory assistant from my former school use silver nitrate for this

Fery - 29-4-2020 at 11:08

Bedlasky - yes, Lapis is safer but must be applied locally for few days/weeks. HNO3 only once was enough.
Mackolol - it was very efficient, just if I overexposed then it slightly burned for some time but not too much. Wart always disappeared.
Today I suggest more gently methods like Verrumal available in my country (fluorouracyl which is cytostatic and blocks virus replication+ salicylic acid in dermatolytical concentration which disrupts and dissolves keratine and keratinocytes) - requires approx 1 month of local treatment. Or liquid nitrogen. Concentrated formic acid too (recently I saw 1 new antiwart medical IIRC of 5 ml which price was 3 fold of 1 L of 85% formic acid from chem supplier).
There is usually a problem that the virus persists somewhere in the human body so even if you win against 1 wart there will be soon created another one at different location

If you have not only 1 wart but a lot of them, there could be probably weak immunity (or very aggressive virus).

Refinery - 3-5-2020 at 23:41

So you produced leather nitrate.

Minor spills are not that biggie, they dissipate in few days. I've got mine too.

Tsjerk - 4-5-2020 at 02:10

Quote: Originally posted by Fery

There is usually a problem that the virus persists somewhere in the human body so even if you win against 1 wart there will be soon created another one at different location

If you have not only 1 wart but a lot of them, there could be probably weak immunity (or very aggressive virus).

These papilloma viruses do not enter the body, and therefore don't persist inside the body. They spread via skin lost from warts, they are very stable outside the body and stay infectious for a very long time.

If you had warts on for example your hands and they keep coming back on different spots... Maybe you should take a day or two off and give your house a really proper cleaning.

chemist1243 - 5-3-2021 at 06:55

Lol, first time? You’re fine.

ChemTalk - 5-3-2021 at 08:31

Like the others said, you will be fine. As a side note, just getting near 68% nitric acid was enough to almost destroy one of my nitrile gloves I was wearing, and there wasn't even direct contact

Also, 30% hydrogen peroxide can leave scary looking white patches. I believe it is oxidizing / burning your skin. It happened to me once on my finger, but it didn't hurt and it went away in a few hours.

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Fyndium - 5-3-2021 at 14:20

I've noted that 30% H2O2 actually stings a lot when it gets onto skin. My usual way of exposure is handling a bottle of it, and when I pour or handle the cap, there will always be that one damn droplet that flows down the side of the bottle, and once you pick it up, you smear it on your fingers, and within a minute you feel that stingy feeling and see white patches on your skin.

Unless I'm handling something toxic or bioaccumulating stuff, I usually just go bare handed, because I've melted my fair share of all kinds of gloves and slipped some glassware due to bad grip. If it's too bad, I look through compatibilities before touching it. A good practice for limiting contamination is to immediately wipe all drops, leaks and spills and the neck of a flask or bottle when handling them.

Xanax - 18-5-2021 at 01:14

Once I was trying to remove my fingerprints with nitric acid, but the finger tops healed and the prints are still there.

But I Have an ugly burn scar on my arm, from nitric acid...

[Edited on 2021-5-18 by Xanax]

Aloesci - 18-5-2021 at 03:59

My Conc. Nitric acid yellow marks stayed on my hands for about two weeks!

I was kinda happy that I'd made concentrated nitric so i didn't take enough care when dissasembling the glassware. (no gloves because i didnt want flaming nitrile burning my skin)
I think it depends how long it was on your skin and how many layers deep it penetrated.