help on dot pt (1 Viewer)

[Sirius Black]

Analyse info form secondary srouces ot assess the use of neutralisation reactions as a safety measure or to minimise damage in accidents or chemical spills
For the second part, it wasn't too hard - we can just talk about hose amphiprotic ions right?
For the first part, I even didn't know what was a safety measureD:

 

[currysauce]

aphiprotic ions.... right?

anyway

Neutralisation reactions are good for chemical spills... blah blah but a negative is that they shouldn't be used for spills regarding humans. As you must know, neutralisation is exothermic, so adding a base to say spilt HCl on urself isn't a good idea, as it would probably cause more burns. Thus assessing this, neutralisation is good for chemical spills as it will remove the acid/base properties, but it shouldn't be carried out for chemical accidents (involving the human body).

I think my notes go on to say like, the best course of action for an acid spill is sodium carbonate, the best course for a base spill is vinegar. As always, wearing safety gear is must because of the vigourous nature. So... i'll leave it up to you to process this, extract what u want, and make an assessment.

hope this helps... my teacher was a bitch about this dotpoint.

 

[HotShot]

no

say you got an acid spill on your skin, naturally a strong base will neutralise it, but since neutralisation is exothermic, then you will burn your skin. The same will happen basically to all bases addes as their all neutralisation reactions. The best method is to flush it down with water, heaps of water. Also sodium hydrogen carbonate can be used as its amphiprotic, can act as a base or acid.

 

[Sirius Black]

If stuff like HCl spills on ur skin, you have to use NaHCO3 to neutralise it even tho the reaction is exothermic

 

[currysauce]

why would u have to use that specific base?....

water is the best course, think about it

neutralisation is exothermic, thus adding a base to an already "burning" acid isn't going to help... water is the best course of action for chemical accidents regarding acid/base spills, just use lots of it

 

[xiao1985]

just a note: if u ever got acid in any part of ur body, wash it with large quantity of water immediately... contrary to popular belief, it does jsut burn a hole thru ur hand in .05 of a second (not with 1M acid any way) but it will eventually burn thru it...

nuetralisation of chemical spill refers more to the spill of chemicals on tables etc.. use amphiprotic, substances, as if u use water: only dilute the acid/base, if u use cloth... very bad... the acid/base actaully saoks into cloth and atks next thing it touches (never use ur coat/shirt to wipe acid...)

 

[thunderdax]

Also, with large acidic spills in the environment, solid calcium carbonate is good because the solid part also stops leakages.

 

[Sirius Black]

Also, with large acidic spills in the environment, solid calcium carbonate is good because the solid part also stops leakages.

will CaO(s) be too strong to use for neutralising acids

hmm, by the way, what does it mean by "a safety measure"?

 

[jamesy_1988]

Hey,

Yeah they do clean up major spills using a neutralisation reaction. But the use of neutralising chemicals is monitored very strictly as to the salt that will be formed and the effects it has on the environment. My uncle is in the EPA so I'll ask him about it, so check back here cos I'll post any info he gives me on it here.

As to acids on your skin, remeber that the reaction of water on a concenrated acid is quite exothermic, though I would still prefer to use water over a base (remember heat of reaction values).

Hope that this may have hepled in some way

Jamesy

 

[adrenaline88]

Hey there,
Just some quick points about medical treatment of acid burns. Before any neutralisation, irrigation with copious amounts of water is required.Burns caused by nasties such as HF ARE neutralised at the Accident & Emergency Department. They often use topical calcium gluconate for skin burns. If the burns are extensive, subcutaneous infiltration of calcium gluconate is needed to ensure damaged area does not spread (because burns from HF often lead to gangrene).

But the actual burns themselves aren't the biggest problems- the electrolyte imbalance (in particular for HF burns, low calcium and magnesium + high potassium) are the biggest worry.

So basically, acid burns ARE neutralised using calcium gluconate (for the most part, by doctors). Often certain factories have topical calcium gluconate in stock for immediate first aid. I've also read somewhere that soaking the burnt area in a solution of mylanta on the way to the hospital is a substitute for calcium gluconate gel.

 

[ice_lord]

our teacher gave us the department rules/guidelines for chemical handling (or whatever lame name they give it) which is published for teachers and science assistants, and gives details of how chemicals must be stored, how spills must be cleaned and all that mumbo jumbo.

I don't remember exactly, but there's something you're not supposed to dilute...

if you're in a government school, ask your teacher for that guide, it's really good.

 

[helper]

Be aware of the Material Safety Data Sheet (MSDS) for the chemical being used and follow safety guidelines. Which are basically what the people above have said.

Eg Hydrochloric acid
http://www.chemsupply.com.au/files/catalog/1CHC1.pdf

Sodium Hydroxide
http://www.chemsupply.com.au/files/catalog/1CHBZ.pdf

The dilution rule is always add the concentrated acid to water, to allow heat dissipation.