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Chemistry:The Central Science
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#Post#: 505--------------------------------------------------
Water and acid
DIR By: Chris
Date: August 6, 2012, 7:52 pm
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Why is adding water to acid very harmful, and adding acid to
water isnt harmful??
#Post#: 534--------------------------------------------------
Re: Water and acid
DIR By: younis pandit
Date: August 16, 2012, 8:13 am
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Adding water to acid is highly exothermic rxn ,actually acid
sputtering occurs; while the reverse does not invovle sputtering
.
#Post#: 547--------------------------------------------------
Re: Water and acid
DIR By: Chris
Date: August 21, 2012, 5:34 am
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Hmmm im not satisfied
My question is: why acid sputtering will happen when you add
water to acid, but it wont happen when you add acid to water?
#Post#: 553--------------------------------------------------
Re: Water and acid
DIR By: Michel
Date: August 23, 2012, 12:13 am
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I wont answer this question directly, but I will give some tips:
1. Write the equation of what happens when a pure acid, say
H2SO4 is added to water
2. What is the limiting reactant when you add acid to water?
What is the limiting reactant when you add water to acid?
3. What effect do you think the specific heat capacity of H2O
have on the temperature change?
#Post#: 565--------------------------------------------------
Re: Water and acid
DIR By: Chris
Date: August 26, 2012, 9:20 am
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1. When you add pure H2SO4 to water, its ions are produced and
they are hydrated
2. When water is added to acid, limiting reactant is water, when
acid is added to water, limiting reactant is acid.
3. Dont know :-/
#Post#: 571--------------------------------------------------
Re: Water and acid
DIR By: rahul dahiya
Date: August 26, 2012, 10:21 am
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during dilution the heat changes some of the water to
steam explosively which can splash the acid on our
face or clothes and cause acid burns
#Post#: 581--------------------------------------------------
Re: Water and acid
DIR By: Michel
Date: August 28, 2012, 3:01 pm
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--- Quote from: Chris link ---
>
> 1. When you add pure H2SO4 to water, its ions are produced and
they are hydrated
> 2. When water is added to acid, limiting reactant is water,
when acid is added to water, limiting reactant is acid.
> 3. Dont know :-/
>
--- End Quote ---
Your answers 1 and 2 are correct.
Water has a comparatively high specific heat capacity. When a
strong acid is added to an excess of water, the heat of dilution
is evolved. Due to the high heat capacity of the water, the
temperature change isn't much hence the solution wont boil and
splatter. This isn't the case when water is added to a solution
of a strong acid. In this case the acid is the limiting
reactant, the heat capacity of the solution is comparatively
low, the acid solution boils due to the heat of dilution.
#Post#: 588--------------------------------------------------
Re: Water and acid
DIR By: rahul dahiya
Date: August 30, 2012, 11:27 am
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becausewhen water is added to concentrated acid to
dilute it ,a large amount of heat is evolved at once.
this heat changes some of the water to steam explosively
which can splash the acid on our face or clothesand
cause acid burns .
but when a concentrated acid is added to waterfor
preparing dilute acid then the heat evolveg gradually ,
and easily absorbed by the large large amount of water
to which acid is being added
#Post#: 616--------------------------------------------------
Re: Water and acid
DIR By: Chris
Date: September 6, 2012, 8:28 pm
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Thanks for replies i can understand it now ;)
#Post#: 707--------------------------------------------------
Re: Water and acid
DIR By: Shiva
Date: September 24, 2012, 5:14 am
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Well, not all acids are dangerous for dilution. Acids which are
hygroscopic in nature only posses danger when mixing with water.
The obvious example is, Sulfuric acid. Some other examples are
Perchloric acid, chloric acid etc.... That's why these acids are
good dehydrating agent. Hydrochloric acid or Nitric acid do not
possess any problem and can dilute them very easily. Hope this
is clear.
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