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Why is water added to concentrated sulphuric acid in order to dilute it?
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May Ramallosa
Why is water added to concentrated sulphuric acid in order to dilute it?
When one adds concentrated sulphuric acid (or any other concentrated acid) to water, a large amount of heat is produced. Hence, it is always recommended to dilute the concentrated acid in small doses with continuous cooling and stirring. The reason this occurs is due to the large amount of energy released in the hydration reaction of concentrated ions. So, it is always safer to add acid to water dropwise with constant stirring and not water to acid directly.
When one adds concentrated sulphuric acid (or any other concentrated acid) to water, a large amount of heat is produced. Hence, it is always recommended to dilute the concentrated acid in small doses with continuous cooling and stirring. The reason this occurs is due to the large amount of energy released in the hydration reaction of concentrated ions. So, it is always safer to add acid to water dropwise with constant stirring and not water to acid directly.
add the acid to the water. If you put water into concentrated sulphuric acid (98%) the water will get so hot that it boils violently splashing hot concentrated sulphuric acid and partly diluted acid everywhere, including your hands, clothing and face.
add the acid to the water. If you put water into concentrated sulphuric acid (98%) the water will get so hot that it boils violently splashing hot concentrated sulphuric acid and partly diluted acid everywhere, including your hands, clothing and face.
As the water is with pH 7 means it is a neutral substance .on adding water in H2SO4 the dilution occurs without chage in pH of acid towards basic pH so watee is used in dilution of acids
As the water is with pH 7 means it is a neutral substance .on adding water in H2SO4 the dilution occurs without chage in pH of acid towards basic pH so watee is used in dilution of acids
Water is NEVER added to Concentrated Sulphuric Acid as it is an exothermic reaction and releases a large amount of heat energy. It also results in spurting of the acid, which can burn your skin.
Concentrated Sulphuric acid is added to water in small amounts and that too with constant stirring and cooling.
I have tried to summarize and make it short and sweet :)
Water is NEVER added to Concentrated Sulphuric Acid as it is an exothermic reaction and releases a large amount of heat energy. It also results in spurting of the acid, which can burn your skin.
Concentrated Sulphuric acid is added to water in small amounts and that too with constant stirring and cooling.
I have tried to summarize and make it short and sweet :)
Two important factors are involved in this question. One is that concentrated sulphuric acid has a very high density compared to water. Density = 1.84 g/cc (water = 1.00 of course) and secondly the heat of hydration of conc. sulphuric acid is quite large.
So when you add acid to water it immediately begins sinking to the bottom of the vessel all the while becoming more diluted. A lot of heat is generated in the dilution reaction but it is spread out over the height of the water column and generally causes no trouble. (Just don’t start with hot water.) Preferably the water vessel should be relatively deep to allow distribution of the heat over a greater height.
In the reverse situation when water is added to conc. H2SO4, because of density differences, the water floats on the acid. Where the two are touching and mixing is poor, the temperature can get above boiling thus causing a steam explosion of boiling water and acid. Very dangerous.
The total heat generated is the same in either case but it is a question of distribution.
This exothermic reaction can also be quite serious with concentrated phosphoric acid and similar precautions need to be taken. Not true with concentrated HCl though, as even the most concentrated acid is only 38% HCl, so it is already diluted. Some temperature rise will occur but nothing serious. You cannot obtain 100% HCl as a liquid at room temperature and pressure.
Two important factors are involved in this question. One is that concentrated sulphuric acid has a very high density compared to water. Density = 1.84 g/cc (water = 1.00 of course) and secondly the heat of hydration of conc. sulphuric acid is quite large.
So when you add acid to water it immediately begins sinking to the bottom of the vessel all the while becoming more diluted. A lot of heat is generated in the dilution reaction but it is spread out over the height of the water column and generally causes no trouble. (Just don’t start with hot water.) Preferably the water vessel should be relatively deep to allow distribution of the heat over a greater height.
In the reverse situation when water is added to conc. H2SO4, because of density differences, the water floats on the acid. Where the two are touching and mixing is poor, the temperature can get above boiling thus causing a steam explosion of boiling water and acid. Very dangerous.
The total heat generated is the same in either case but it is a question of distribution.
This exothermic reaction can also be quite serious with concentrated phosphoric acid and similar precautions need to be taken. Not true with concentrated HCl though, as even the most concentrated acid is only 38% HCl, so it is already diluted. Some temperature rise will occur but nothing serious. You cannot obtain 100% HCl as a liquid at room temperature and pressure.
Water is added to concentrated Sulphuric acid as other things when added to the acid like rocks do not dilute it.
Moreover Water is added to sulphuric acid and not the reverse in order to cause spurting of the acid and get painful burns on your skin if that is your mere wish!
It is the heat of the exothermic reaction that turns water into steam which gives way to such accidents. The opposite of the said method in the question is done as sulphuric acid is added dropwise to water alongside constant stirring of the mixture to dilute it.
Water is added to concentrated Sulphuric acid as other things when added to the acid like rocks do not dilute it.
Moreover Water is added to sulphuric acid and not the reverse in order to cause spurting of the acid and get painful burns on your skin if that is your mere wish!
It is the heat of the exothermic reaction that turns water into steam which gives way to such accidents. The opposite of the said method in the question is done as sulphuric acid is added dropwise to water alongside constant stirring of the mixture to dilute it.
You never ever add water to a concentrated acid especially not with H2SO4 !
Always the revers :
Always add the concentrated acid to the water, under stirring, and cooling if necessary.
Why ?
Because the (physical) reaction is obvious very exothermic,
and water is density +- 1, and H2SO4 98% = +- 1.83 kg/l so if you add the water it will stay on top, laying on the acid, all of the reaction happens only on that interface surface, the water will quickly boil and become steam and erupt out of the flask like a volcano!
If you do it correctly, put water in an Erlenmeyer flask and then add the acid slowly you’ll see the acid disperse fast while trying to reach the bottom; so obvious permanent stirring is best, and depending on how high a concentration you’re prepping and how much of it, you may need to stop adding the acid in between, and put the flask under running water or a water bath to cool it down.
You never ever add water to a concentrated acid especially not with H2SO4 !
Always the revers :
Always add the concentrated acid to the water, under stirring, and cooling if necessary.
Why ?
Because the (physical) reaction is obvious very exothermic,
and water is density +- 1, and H2SO4 98% = +- 1.83 kg/l so if you add the water it will stay on top, laying on the acid, all of the reaction happens only on that interface surface, the water will quickly boil and become steam and erupt out of the flask like a volcano!
If you do it correctly, put water in an Erlenmeyer flask and then add the acid slowly you’ll see the acid disperse fast while trying to reach the bottom; so obvious permanent stirring is best, and depending on how high a concentration you’re prepping and how much of it, you may need to stop adding the acid in between, and put the flask under running water or a water bath to cool it down.
Water is lighter than sulphuric acid, and mixing water with sulphuric acid releases heat. Adding water to acid can cause a boundary layer to form, as the water floats atop the acid, and intense heat develops at the boundary layer. This can cause the water to boil and spit water-acid solution into the unwise chemist’s face, or even cause uneven heating that shatters glassware.
My chemistry teacher always told us, “If you’re doing what you oughta, you’ll add the acid to the water. May your rest be long and placid if you add the water to the acid.”
Water is lighter than sulphuric acid, and mixing water with sulphuric acid releases heat. Adding water to acid can cause a boundary layer to form, as the water floats atop the acid, and intense heat develops at the boundary layer. This can cause the water to boil and spit water-acid solution into the unwise chemist’s face, or even cause uneven heating that shatters glassware.
My chemistry teacher always told us, “If you’re doing what you oughta, you’ll add the acid to the water. May your rest be long and placid if you add the water to the acid.”
To dilute and acid, you add water. It increases the pH value. Since sufluric acid has a Low pH value, and water has a pH value of 7, neutral, it can increase the pH value, diluting it
To dilute and acid, you add water. It increases the pH value. Since sufluric acid has a Low pH value, and water has a pH value of 7, neutral, it can increase the pH value, diluting it
When one adds concentrated sulphuric acid (or any other concentrated acid) to water, a large amount of heat is produced. Hence, it is always recommended to dilute the concentrated acid in small doses with continuous cooling and stirring. The reason this occurs is due to the large amount of energy released in the hydration reaction of concentrated ions. So, it is always safer to add acid to water dropwise with constant stirring and not water to acid directly.
When one adds concentrated sulphuric acid (or any other concentrated acid) to water, a large amount of heat is produced. Hence, it is always recommended to dilute the concentrated acid in small doses with continuous cooling and stirring. The reason this occurs is due to the large amount of energy released in the hydration reaction of concentrated ions. So, it is always safer to add acid to water dropwise with constant stirring and not water to acid directly.
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NO DO NOT DO IT THAT WAY
add the acid to the water. If you put water into concentrated sulphuric acid (98%) the water will get so hot that it boils violently splashing hot concentrated sulphuric acid and partly diluted acid everywhere, including your hands, clothing and face.
NO DO NOT DO IT THAT WAY
add the acid to the water. If you put water into concentrated sulphuric acid (98%) the water will get so hot that it boils violently splashing hot concentrated sulphuric acid and partly diluted acid everywhere, including your hands, clothing and face.
More
VOTE
As the water is with pH 7 means it is a neutral substance .on adding water in H2SO4 the dilution occurs without chage in pH of acid towards basic pH so watee is used in dilution of acids
As the water is with pH 7 means it is a neutral substance .on adding water in H2SO4 the dilution occurs without chage in pH of acid towards basic pH so watee is used in dilution of acids
More
VOTE
Water is NEVER added to Concentrated Sulphuric Acid as it is an exothermic reaction and releases a large amount of heat energy. It also results in spurting of the acid, which can burn your skin.
Concentrated Sulphuric acid is added to water in small amounts and that too with constant stirring and cooling.
I have tried to summarize and make it short and sweet :)
Hope it helps!
Water is NEVER added to Concentrated Sulphuric Acid as it is an exothermic reaction and releases a large amount of heat energy. It also results in spurting of the acid, which can burn your skin.
Concentrated Sulphuric acid is added to water in small amounts and that too with constant stirring and cooling.
I have tried to summarize and make it short and sweet :)
Hope it helps!
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You add wáter to dilute it (acid to wáter) to get a definite concentration for example:
H2SO4 in the car batteries is not concentrated. So you need to dilute it to that necessary concentration.
You add wáter to dilute it (acid to wáter) to get a definite concentration for example:
H2SO4 in the car batteries is not concentrated. So you need to dilute it to that necessary concentration.
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Two important factors are involved in this question. One is that concentrated sulphuric acid has a very high density compared to water. Density = 1.84 g/cc (water = 1.00 of course) and secondly the heat of hydration of conc. sulphuric acid is quite large.
So when you add acid to water it immediately begins sinking to the bottom of the vessel all the while becoming more diluted. A lot of heat is generated in the dilution reaction but it is spread out over the height of the water column and generally causes no trouble. (Just don’t start with hot water.) Preferably the water vessel should be relatively deep to allow distribution of the heat over a greater height.
In the reverse situation when water is added to conc. H2SO4, because of density differences, the water floats on the acid. Where the two are touching and mixing is poor, the temperature can get above boiling thus causing a steam explosion of boiling water and acid. Very dangerous.
The total heat generated is the same in either case but it is a question of distribution.
This exothermic reaction can also be quite serious with concentrated phosphoric acid and similar precautions need to be taken. Not true with concentrated HCl though, as even the most concentrated acid is only 38% HCl, so it is already diluted. Some temperature rise will occur but nothing serious. You cannot obtain 100% HCl as a liquid at room temperature and pressure.
Two important factors are involved in this question. One is that concentrated sulphuric acid has a very high density compared to water. Density = 1.84 g/cc (water = 1.00 of course) and secondly the heat of hydration of conc. sulphuric acid is quite large.
So when you add acid to water it immediately begins sinking to the bottom of the vessel all the while becoming more diluted. A lot of heat is generated in the dilution reaction but it is spread out over the height of the water column and generally causes no trouble. (Just don’t start with hot water.) Preferably the water vessel should be relatively deep to allow distribution of the heat over a greater height.
In the reverse situation when water is added to conc. H2SO4, because of density differences, the water floats on the acid. Where the two are touching and mixing is poor, the temperature can get above boiling thus causing a steam explosion of boiling water and acid. Very dangerous.
The total heat generated is the same in either case but it is a question of distribution.
This exothermic reaction can also be quite serious with concentrated phosphoric acid and similar precautions need to be taken. Not true with concentrated HCl though, as even the most concentrated acid is only 38% HCl, so it is already diluted. Some temperature rise will occur but nothing serious. You cannot obtain 100% HCl as a liquid at room temperature and pressure.
More
VOTE
Water is added to concentrated Sulphuric acid as other things when added to the acid like rocks do not dilute it.
Moreover Water is added to sulphuric acid and not the reverse in order to cause spurting of the acid and get painful burns on your skin if that is your mere wish!
It is the heat of the exothermic reaction that turns water into steam which gives way to such accidents. The opposite of the said method in the question is done as sulphuric acid is added dropwise to water alongside constant stirring of the mixture to dilute it.
Water is added to concentrated Sulphuric acid as other things when added to the acid like rocks do not dilute it.
Moreover Water is added to sulphuric acid and not the reverse in order to cause spurting of the acid and get painful burns on your skin if that is your mere wish!
It is the heat of the exothermic reaction that turns water into steam which gives way to such accidents. The opposite of the said method in the question is done as sulphuric acid is added dropwise to water alongside constant stirring of the mixture to dilute it.
More
VOTE
It is NOT !
You never ever add water to a concentrated acid especially not with H2SO4 !
Always the revers :
Always add the concentrated acid to the water, under stirring, and cooling if necessary.
Why ?
Because the (physical) reaction is obvious very exothermic,
and water is density +- 1, and H2SO4 98% = +- 1.83 kg/l so if you add the water it will stay on top, laying on the acid, all of the reaction happens only on that interface surface, the water will quickly boil and become steam and erupt out of the flask like a volcano!
If you do it correctly, put water in an Erlenmeyer flask and then add the acid slowly you’ll see the acid disperse fast while trying to reach the bottom; so obvious permanent stirring is best, and depending on how high a concentration you’re prepping and how much of it, you may need to stop adding the acid in between, and put the flask under running water or a water bath to cool it down.
It is NOT !
You never ever add water to a concentrated acid especially not with H2SO4 !
Always the revers :
Always add the concentrated acid to the water, under stirring, and cooling if necessary.
Why ?
Because the (physical) reaction is obvious very exothermic,
and water is density +- 1, and H2SO4 98% = +- 1.83 kg/l so if you add the water it will stay on top, laying on the acid, all of the reaction happens only on that interface surface, the water will quickly boil and become steam and erupt out of the flask like a volcano!
If you do it correctly, put water in an Erlenmeyer flask and then add the acid slowly you’ll see the acid disperse fast while trying to reach the bottom; so obvious permanent stirring is best, and depending on how high a concentration you’re prepping and how much of it, you may need to stop adding the acid in between, and put the flask under running water or a water bath to cool it down.
More
VOTE
Water is lighter than sulphuric acid, and mixing water with sulphuric acid releases heat. Adding water to acid can cause a boundary layer to form, as the water floats atop the acid, and intense heat develops at the boundary layer. This can cause the water to boil and spit water-acid solution into the unwise chemist’s face, or even cause uneven heating that shatters glassware.
My chemistry teacher always told us, “If you’re doing what you oughta, you’ll add the acid to the water. May your rest be long and placid if you add the water to the acid.”
Water is lighter than sulphuric acid, and mixing water with sulphuric acid releases heat. Adding water to acid can cause a boundary layer to form, as the water floats atop the acid, and intense heat develops at the boundary layer. This can cause the water to boil and spit water-acid solution into the unwise chemist’s face, or even cause uneven heating that shatters glassware.
My chemistry teacher always told us, “If you’re doing what you oughta, you’ll add the acid to the water. May your rest be long and placid if you add the water to the acid.”
More
VOTE
To dilute and acid, you add water. It increases the pH value. Since sufluric acid has a Low pH value, and water has a pH value of 7, neutral, it can increase the pH value, diluting it
To dilute and acid, you add water. It increases the pH value. Since sufluric acid has a Low pH value, and water has a pH value of 7, neutral, it can increase the pH value, diluting it
More
VOTE