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dEdt
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Why does a can of soda "explode" when it's shaken? I looked online, but all the explanations were either very hand-wavy, or looked very wrong. Thanks!
ShawnD said:CO2 is dissolved in the liquid. Liquids cannot dissolve as much gas when the liquid is agitated.
This concept is used in labs all the time. Gas can be removed from a liquid by shaking it at high speeds using ultrasound.
Best explanation I've heard is that shaking increases the kinetic energy of both the liquid and the gas. When the molecules are moving around faster, it's harder for them to grab each other. This makes sense because it's exactly what happens when a liquid is heated - hot liquids dissolve less gas.
dEdt said:The pressure inside the can increases with depth, so the lower portions of the can should hold more gas than the shallower parts.
the pressure might not be enough to keep the gas in suspension
Axillary question: why does tapping the can help?
skeptic2 said:The explanation I was given is that the CO2 in the liquid exerts a certain pressure per unit area of the surface. In shaking the liquid the surface area of the liquid increases dramatically and so does the total pressure.
Borek said:but concentration in a given temperature depends only on the pressure (Henry's law). Whatever happens when the can is shaken seems to be effect of oversaturation and nucleation.
It won't. When people pop open a bottle of bubbly wine, they will often tap the glass with a spoon to build pressure. That's also a jerk move to do to someone's beer; tap the side of it when they leave the table so it goes flat very quickly.why does tapping the can help?
ShawnD said:When something is in a oversaturated condition and some agitation causes it to crash out, isn't that usually a process that doesn't reverse itself?
When a soda can is shaken, the carbon dioxide gas that is dissolved in the liquid becomes highly pressurized. This pressure builds up and causes the can to explode when the seal is broken.
Shaking the can causes the carbon dioxide gas to mix with the liquid, increasing the concentration of gas molecules. This increase in concentration leads to an increase in pressure inside the can.
Yes, a soda can can explode without being shaken if it is exposed to high temperatures or if the can is damaged in some way. In these cases, the pressure inside the can can build up and cause it to burst open.
Shaking a soda can can be dangerous if the can is already under high pressure. The sudden release of pressure when the can is opened can cause the liquid to spray out, potentially causing injury. It is always important to handle soda cans with caution.
When a soda can explodes, the sudden release of pressure causes the liquid to rapidly expand and turn into gas. This gas expands and pushes the liquid out of the can, creating the explosion. The soda itself does not undergo any chemical changes during this process.