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De carbonating a soft drink (1 Viewer)

Shoom

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Hi
I must de carbonate a soft drink using two methods.
First one I will be doing is heating, the thing is I cant think of a method to heat up the softdrink. Anyone know?

Also what should I do for the second method?
 

yer8899

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*Baby-K* said:
I've never done chem, but can't you just pour it into a pot and put on the stove?
i think the best way to heat up a soft drink would be to put the bottle or can of soft drink in a water basin and heat the water. is this a question in a past paper?
 

wixxy2348

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we didnt use heating.. apparently it takes a very long time as u have to use a water bath

our two methods were slowly adding salt
and shaking (transferring whats in say a 390 mL bottle into a 2 L bottle and then shaking until no bubbles remain)

both were effective.
 

Buttigieg

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Well, we poured 250mL of the contents in a flask and heated it in a water bath (using hot plate). Also, for a control, we heated 250mL of water. By doing this, we could minus the amount of weight lost due to evaporation.

We also took into account that we only used 250mL of how ever much softdrink there was, and so we did calculations to work out what the loss would be for the whole can.

Also, dont forget to weigh after every (well, almost every) step.
 

Shoom

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What do I use for a water basin, cant I just sticky my soft drink in the water nath and heat the water bath up using a bunsen burner?

For the heating method, when do I weigh it? Should I just leave it for 30minutes then weigh it?
 

SkimDawg

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Shoom said:
For the heating method, when do I weigh it? Should I just leave it for 30minutes then weigh it?
Yeah do that, i think u need to find the moles / volume of CO2 escaped. I remember when i did this prac, i heated it, drank it and tasted like shit, and spilt it everywhere. What a failure of a day. I didn't get the numbers down either -_-
 

Twickel

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How can I heat it the school has only the basic equipment
 

Buttigieg

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Twickel said:
How can I heat it the school has only the basic equipment
just use a bunsen burner...u guys do have a bunsen burner right?
and poor the contents in a flask
 

Shoom

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Thats in accurate, I dont know tge weight of the bottle etc.
 

Buttigieg

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Shoom said:
Thats in accurate, I dont know tge weight of the bottle etc.
use a certain amount, like 250mL and poor that amount accuratly into a flask, then carry out the experiment on that 250mL, then calculate what it would be if you used the entire contents...ie, weigh the bottle and stuff before hand too, and also after pooring the 250ml out to see how much you have left
 

Shoom

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Hey what about this.

Forget the mass of the bottle, just pour the 250mL into a beaker, before I pour the drink into the beaker, I should weigh the beaker then 250ml+weight of beaker = mass before experiment. Then the mass difference e is CO2 lost.


Is that accurate and valid?
 

Buttigieg

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Shoom said:
Hey what about this.

Forget the mass of the bottle, just pour the 250mL into a beaker, before I pour the drink into the beaker, I should weigh the beaker then 250ml+weight of beaker = mass before experiment. Then the mass difference e is CO2 lost.


Is that accurate and valid?
Perfectly fine mate!
 

Shoom

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Well WTF am I going to do.

if anyone knows anything please tell me.
 

crammy90

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what i did was set it up like you weould refluxing right.
what happens is the water and CO2 rise up the condensor with cool water running through it. The water condenses and falls back down. The CO2 keeps going out...
was that not right?
i guess you could add indicator as the CO2 reacts with water for form carbonic acid. If theres no CO2 the indicator will have changed to that colour of its non-acidic conditions.
 

philxe

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1) theres the shaking it then weigh before and after.
2) Heat it, but don't use direct flame since it can evaporate the water and disturb the result
3) Adding salt to the carbonated water also stimulate the co2 escaping, however you need to weigh how much you put in accurately.
 

theprodigy

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class did this prac .
was absent though :(

1) heating it. we did just room temperature
2) just leave the cap open over the weekend.
 

crammy90

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do u rekon in an exam it would be worth to write for the method
i) place bottle of distilled water and a bottle of softdrink (unopened) on scales and weighed each
ii) placed each in a water bath and heated on low, re-measuring the softdrink untill there appeared to be no mass change (took water off heat aswell at exact same time when weighing soft drink). Both were heated at same temp in same conditions
iii) DID: mass(water intiially) - mass (water final) = mass H2O lost
iv) DID: mass(softdrink initially) - mass(water final) = amount of CO2 lost
--- im thinking that would be
  • Reliable: do it many times, all the class got the same results
  • Validity: comparing with the water gives us the ability to be calculating only the CO2 lost and not water evaporated. All experimental variables were controlled (heat) and so is a valid experimental design. We re-heated untill the mass change in the softdrink was decreasing at the rate of the water exactly. We continued re-weighing untill the softdrink decrease was the same for the water for 3 times to indicate no more CO2 was left at all
  • Accuracy: scales were to 0.01g which are accurate.
Just an idea lol...do this or just stick to the normal leave bottle open untill mass is decreasing slighlty, calculate CO2 and then just say in validity: wasnt valid as didnt account for water loss...
confusing experiment yasss
 

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