Normal Coke floating in a tank of water?

Ender

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Jul 24, 2001
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It's common knowledge that Diet Coke floats while Coke Classic sinks simply because Diet Coke contains aspartane. However, my chemistry teacher showed my class that Classic Coke can also float. He asked us how this could be but nobody could figure it out. Does anyone know how this could happen?
 

Ime

Diamond Member
May 3, 2001
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Originally posted by: Ender
It's common knowledge that Diet Coke floats while Coke Classic sinks simply because Diet Coke contains aspartane. However, my chemistry teacher showed my class that Classic Coke can also float. He asked us how this could be but nobody could figure it out. Does anyone know how this could happen?

Salt Water?
 

ravana

Platinum Member
Jul 18, 2002
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Originally posted by: Ime
Originally posted by: Ender
It's common knowledge that Diet Coke floats while Coke Classic sinks simply because Diet Coke contains aspartane. However, my chemistry teacher showed my class that Classic Coke can also float. He asked us how this could be but nobody could figure it out. Does anyone know how this could happen?

Salt Water?

That was my thought too
 

Semidevil

Diamond Member
Apr 26, 2002
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well, since this is a science class, all you have to say is "then that means there is a different type of chemical that causes it to float..."

the teacher will be so happy w/ your scientific approach and just move on to the next student...
 

Ender

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Jul 24, 2001
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Well, he threw it in the same tank that the Classic Coke had sunk in and both versions of the Classic Coke were inside the tank at the same time. The floating one and the sinking one in addition to the Diet Coke which also floated, so it can't have anything to do with the water, I don't think.
 

brian_riendeau

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Oct 15, 1999
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If it is not saltwater, maybe he heated up one can to expands its volume slightly and cause it to float.
 

dullard

Elite Member
May 21, 2001
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Originally posted by: Ender
Well, he threw it in the same tank that the Classic Coke had sunk in and both versions of the Classic Coke were inside the tank at the same time. The floating one and the sinking one in addition to the Diet Coke which also floated, so it can't have anything to do with the water, I don't think.
My guess is that he had previously frozen one of the classic cokes. The freezing would cause the can to expand and deform permanently. This is since water is one of the more unusual chemicals that expands when cooled (only true for temperatures below 4°C with water). This permanently expands the aluminum even after the classic coke has returned to room temperature. The difference is subtle. But with a larger volume and the same mass, any previously frozen pop will float.

There could be other explanations, this is just the first I thought of.
 

Gibson486

Lifer
Aug 9, 2000
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Originally posted by: SampSon
He shook up the can.

yeah, shaking it would not effect the weight, but it would effect the density. Atleast that is my theory.
 

Gunslinger08

Lifer
Nov 18, 2001
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Why would it change the density? It's a sealed can. Nothing is changing place, so it's still the same mass in the same volume.
 

Ender

Golden Member
Jul 24, 2001
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One of our hypothesis was that he shook up the can but then he took the sunken Classic Coke and shook it for 5-6 seconds and put it back into the tank. It sank.

However, it is possible that he froze one of the pops, allowed the can to inflate and then let the Coke thaw with a deformed can.

Oh, and the floating Classic Coke was floating for a good 5-6 minutes... well after we left class, so I don't think it could have been shaken enough for the effects to last that long.
 

Gibson486

Lifer
Aug 9, 2000
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Originally posted by: joshsquall
Why would it change the density? It's a sealed can. Nothing is changing place, so it's still the same mass in the same volume.


density is only part of it. While density remains the same, it is not the same through out the whole can. There is still some space for the liquid to move, therefore, teh force boyouncy (sp?) does not remain the same at every point, which makes the can tip and create a force greater than that boyouncy. When you shake the can, all teh molocules disperse everywhere (due to the carbonation?), so density at every part of teh can remains more constant and the liquid doe snot subside or move as much to make it over come the force boyouncy(sp?) of the water.

Keep in mind, i am not a scientist, so i could be totally wrong.