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Old 12-22-2005, 01:25 AM
aLowlyn00b aLowlyn00b is offline
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why does soda burn when you drink it?

why does soda burn when you drink it?
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  #2  
Old 12-22-2005, 01:34 AM
A.R. Cane A.R. Cane is offline
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I believe it the difference in the Ph factor between your mouth, primarily the tongue, and the soda. That's the culpit that makes your eyes burn when you get soap in them, or sometimes even plain water. Usually the difference isn't that great and the sensation quickly abates. Of course w/ the soap in the eye it's usually more acute and the burning lasts much longer because soap tends to have a higher Ph.
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Old 12-22-2005, 01:42 AM
Good Egg Good Egg is offline
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I thought it was the carbonation?
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Old 12-22-2005, 01:52 AM
aLowlyn00b aLowlyn00b is offline
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Quote:
Originally Posted by Good Egg
I thought it was the carbonation?
i thought that at first but I wasnt 100% sure
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Old 12-22-2005, 02:14 AM
Cardinal Cardinal is offline
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I assumed it was the carbonic acid that comes from the carbonation. A chem teacher I worked with pointed out that in the real world, even pure water has a slightly acid pH because of the dissolved CO2 in it. If you force the CO2 in, you get high levels of bitter/tangy acid. That's what makes the soda water so yucky when the soda syrup runs out a the McDonald's. It's also why sodas need so much sweetner. You need it to counterbalance the acid.
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Old 12-22-2005, 07:42 AM
RealityChuck RealityChuck is online now
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Carbon dioxide is the source of the stinging sensation when you drink soda. It immediately combines with water in your mouth to form carbonic acid.
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Old 12-22-2005, 07:46 AM
August West August West is offline
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There is quite a bit of phosphoric acid in most sodas as well.
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Old 12-22-2005, 11:00 AM
Ruken Ruken is offline
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Quote:
Originally Posted by Cardinal
It's also why sodas need so much sweetner. You need it to counterbalance the acid.
I've never noticed seltzer water to be terribly acid-tasting. It's just as carbonated as normal soda, if not more so. I've never checked it's pH, but I'm sure it's of a much higher pH than something like lemmon juice, which produces a different sensation in the mouth.
Quote:
Originally Posted by RealityChuck
Carbon dioxide is the source of the stinging sensation when you drink soda. It immediately combines with water in your mouth to form carbonic acid.
But the CO2 is already in water in the soda. Would a saturated solution of carbonic acid produce that same stinging sensation?
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Old 12-22-2005, 11:41 AM
CookingWithGas CookingWithGas is offline
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But very acidic foods, like orange juice, tomatoes, citrus fruits, or vinegar, do not burn. We usually experience acidic tastes as sour. Malic acid is used to make candy sour, but doesn't burn. Once I got a very tiny taste of battery acid as was struck that the sensation was sour rather than burning (although I imagine it would burn horribly in larger amounts).

How does pH explain why soda burns?
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  #10  
Old 12-22-2005, 03:21 PM
panamajack panamajack is offline
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It isn't the acid, it's the reaction forming bubbles in the mouth (as RealityChuck said). If you really want to feel the pain, hold a bit of soda in your mouth while it's bubbling.

I can barely stand carbonated drinks for this reason.
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  #11  
Old 12-22-2005, 08:13 PM
Guinastasia Guinastasia is online now
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Now see, I love the bubbly little burn you get with carbonation. That's the whole point of drinking pop! Otherwise, I might as well just drink Kool-Aid.
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