dry ice is frozen carbon dioxide< which is i think is -130 degrees C. When water is poured on it it sublimates (turns back into gas and is so cold the fog is white, but, as it warms up it turns clear. carbon dioxide is more dense than air (more heavy than air) so it floats toward the bottom of the tank. the bubbles are more dense than air but less dense than carbon dioxide so they float on the carbon dioxide gas.
@jackcat12345 couple minor notes though you are mostly correct. The sublimation temp of CO2 at 1 atm is roughly -78 deg. C at atmospheric pressure which we are here in Highland Heights KY. As for the vapor you see it is actually water vapor that condenses to form fog. This is due to the cold temperatures of the CO2 as you stated. The reason it clears as you move up is the temperature increases and the fog thins. CO2 is clear as a gas. Your description of the density though is spot on.
@steadfast1984 they are university students actually but the videos are meant for all levels so they normally don't discuss the topics at the university level
@mcjhn it is basically fog that forms by pouring water over the cold dry ice. We use it in the demonstration since it places a visible layer for the bubbles to sit on.
@mcjhn the CO2 cools the water vapor (always present above water) into a fog which you see. It doesn't carry the water into the air exactly but more like cools what is already there.
I didn't see any do it here, but it is possible to freeze the bubbles with the dry ice. I've had it work better with crushed dry ice, but you can get a bubble to freeze when it touches the dry ice- it will pop, but you get a frozen shell, rather than a wet splatter. It is even possible to pick it up with plastic tweezers- at least for a moment.
dry ice is frozen carbon dioxide< which is i think is -130 degrees C. When water is poured on it it sublimates (turns back into gas and is so cold the fog is white, but, as it warms up it turns clear. carbon dioxide is more dense than air (more heavy than air) so it floats toward the bottom of the tank. the bubbles are more dense than air but less dense than carbon dioxide so they float on the carbon dioxide gas.
jackcat12345 6 months ago
@jackcat12345 couple minor notes though you are mostly correct. The sublimation temp of CO2 at 1 atm is roughly -78 deg. C at atmospheric pressure which we are here in Highland Heights KY. As for the vapor you see it is actually water vapor that condenses to form fog. This is due to the cold temperatures of the CO2 as you stated. The reason it clears as you move up is the temperature increases and the fog thins. CO2 is clear as a gas. Your description of the density though is spot on.
sieveb1 6 months ago
interesting
killacam44 1 year ago
wow cool haha
Cheejyg 1 year ago
these are high school students right?
steadfast1984 1 year ago
@steadfast1984 they are university students actually but the videos are meant for all levels so they normally don't discuss the topics at the university level
sieveb1 1 year ago
@sieveb1 what is the stuff that looks like mist and how does it form?
mcjhn 1 year ago
@mcjhn it is basically fog that forms by pouring water over the cold dry ice. We use it in the demonstration since it places a visible layer for the bubbles to sit on.
sieveb1 1 year ago
@sieveb1 so does the subliming CO2 carry tiny water droplets into the air?
mcjhn 1 year ago
@mcjhn the CO2 cools the water vapor (always present above water) into a fog which you see. It doesn't carry the water into the air exactly but more like cools what is already there.
sieveb1 1 year ago
@sieveb1 oh...that's interesting, thanks!
mcjhn 1 year ago
I didn't see any do it here, but it is possible to freeze the bubbles with the dry ice. I've had it work better with crushed dry ice, but you can get a bubble to freeze when it touches the dry ice- it will pop, but you get a frozen shell, rather than a wet splatter. It is even possible to pick it up with plastic tweezers- at least for a moment.
mrericsully 1 year ago
@mrericsully That is actually another demonstration that we do but you are right it is very very cool to play with the bubbles
sieveb1 1 year ago
thats an awsome expirement!!!
ThePokemaster8 1 year ago
@ThePokemaster8 - glad you like it
sieveb1 1 year ago