sulfuric acid safety precautions (1 Viewer)

[erm]

could someone clear this up for me:

why does my textbook say that if you splash some sulfuric acid (concentrated) on your skin, you should run it under water? Isn't the dilution of sulfuric acid extremely exothermic and wouldn't this burn your skin/cause more damage?

What about wiping it off with a paper towel? Would that not be better?

 

[white ferret]

yeah, but the burns you'll get by leaving sulfuric acid on ur skin are much worse. running it under water would mean the acid gets washed off almost immediately, whereas waiting for a paper towl to soak it all up will take wayy longer (esp if your school is like mine and has thin, non-absorbant paper towels), and in the meantime, the acid is eating through your skin.

 

[Undermyskin]

No.

What can I say? Any available methods to reduce the problems H2SO4 poses lead to the release of heat. We have to choose the most pertinent one.

Diluting conc. sulfuric acid with NaHCO3 is only appliable if the spillage is on flat surfaces or in high amount. The reaction is exothermic with the production of CO2 gas. I don't think it's any where near pleasant to feel hot, painful and fizzy at the same time! )

Using dry tower paper is only for the dribblings of acid when using bottles. It's of low amount, not exothermic and well, safe to some extent.

Now you wonder why we don't use dry paper on skin. As you should already know, conc. H2SO4 is a strong oxidizing and dehydrating agent. Its second role, I confirm you, can give any spillage on the skin a lengthy agonising experience. Just look at the dehydrating reaction with sugar and you have some brief idea how our skin might turn. Basically, when coming into contact with ANY living micro-organism and moist substances, H2SO4 is extremely evil. It 'tears off' the chemical components of protein, fats and carbohydrates into much more simple chemicals. As a matter of fact, wiping with paper towel is definitely not possible.

Although the dilution of acid is exothermic, water has very high specific heat capacity (remember Water last year?), hence, the excess water consumes the heat released, cool down, and sort of numb your senses (prove me wrong) of the skin around the burn. That's why they say: use 'running water', it can carry away most of what you concern.

And I assure you, at that concentration, sulfuric is of no harm to both you and environment.

 

[white ferret]

ahh yes, forgot about the dehydrating component.

you'll prob be in too much shock to feel anything.

 

[erm]

cheers "undermyskin" and "white ferret".

So am i correct in the conclusion that while washing with water may hurt, it is the lesser of two evils?

 

[minijumbuk]

Although the dilution of acid is exothermic, water has very high specific heat capacity (remember Water last year?), hence, the excess water consumes the heat released, cool down, and sort of numb your senses (prove me wrong) of the skin around the burn. That's why they say: use 'running water', it can carry away most of what you concern.

Well I wasn't going to try, but now that you've sent a challenge, I shall make an attempt to prove you wrong xD (Although the chances of me failing to do so are quite high, as there is no error, or very insignificant ones)

[arsehole mode]The key here, I think, is not so much of the concern of the large amount of heat released, but rather the ionisation of H2SO4. Heat is insignificant, because you've got like...an endless supply (ok, that was exaggeration... But enough water to cool you down) of cool water... So the specific heat capacity of water isn't too significant. Also, I doubt the 'dilution' will be hot enough to burn you anyway. However, the ionisation can cause a dramatic decrease in pH, and this can irritate skin cells. If acid was spilled near the mouth, large intesties (LOL WTF) or vagina (LOL LOL LOL WTFFFF), they can even cause an imbalance in level of microflora!!! (biology ftw xD)

I think that's the reason why water is used instead of paper towels, since paper towels are SOLID, and can NEVER remove ALL of the conc H2SO4. If H2SO4 is left on the skin, sweat might develop, which can ionise the acid and cause an increase in concentration of H3O+ ions. Water is just...more efficient at washing away any remaining acid molecules.
[/areshole mode]

Okay, I had my fun xD

stuff

Yes, you are.