Neutralization as a safety procedure (1 Viewer)

[~Smurfette~]

Hey everyone!
Does anyone have any information that could clarify this dot-point for me:

Analyze information to asses the use of neutralization reactions as a safety measure or to minimize damage in accidents or chemical spills.

I'm not too sure if it means to asess that neutralization directly with a base is unsuitable as it releases large amounts of heat and causes the spitting of acid into the environment, or if it refers to the neutralization using an amphiprotic substance e.g. sodium bicarbonate. I'm not too sure how to make the assessment - help greatly appreciated!

 

[dead]

u can neutralise with a base but use a weak base so the heat released is kept at a minimum, also use a solid so the acid can be "soaked up" and not spread out causing more damage. Then afterwards, splash lots of water over it and u can clean it up.

sodium carbonate can also be used for neutralising since it is amphiprotic, so it can be used to neutralise both acids and bases which can come in handy if u dont know what substance is spilt on the floor.

hope it helps

 

[serge]

i doubt the heat released is very high at all...
does anyone know any real enthalpy measurements for neutralisation?

 

[dead]

according to conq. chem ..."the enthalpy change, for neutralisation reactions is approx. -56kJ/mol" is that hot? ....lol all i noe is that -ve enthalpy is exothermic and +ve is endothermic. but i guess it depends on what kind of acid and what base reacts.

 

[jetfan]

generally when we talk about chemical spills, we are talking about the container trucks, carrying the higher concentrations, because in school labs, they are diluted heaps. So if you have spilt a large amount of high concentration NaOH, you want to keep the heat liberated to a minimum. Neutralisation is highky exothermic between a strong acid and base, so we use a weak acid to clean it. Also, could you show me with an equation how Na2CO3 is amphiprotic, ta.


--jetfan--

 

[jetfan]

I think you meant sodium Hydrogen carbonate

HCO3- + H2O --> CO3 2- + H3O+

HCO3- + H2O --> H2CO3 + OH-

 

[Dreamerish*~]

You need to know that neutralisation is an exothermic reaction so you can say that you can't pour base onto your hand if you touched some acid. I don't think it matters too much that heat is released when the spill is located on the ground.

 

[~Smurfette~]

yeah, sodium bicarbonate is the same thing as sodium hydrogen carbonate..just to clarify that if it comes up in the exam!

 

[wanton-wonton]

i doubt the heat released is very high at all...
does anyone know any real enthalpy measurements for neutralisation?

Consider the neutralisation reaction:
HCl(aq) + NaOH(aq) ---> NaCl(aq) + H2O(l)
H+ + OH- ---> H2O, ΔH = -57kJ/mol