A Sublime Way to Chill Out

 

Dry Ice pellets

Dry Ice pellets

Sublime has a number of meanings, such as lofty, noble, above the rest.  However, in the world of chemistry, sublime means to go directly from solid to gas, do not pass liquid, do not collect in a flask.  The classic example of this is dry ice, solid carbon dioxide.

Carbon dioxide gas is everywhere (a fact that sends Al Gore into conniptions) as the product of combustion and biological use of carbon sources like sugars and fats. This means it is easily available for scientific study. As scientists sought to chill this gas, they found that they could not liquefy it at atmospheric pressure, no matter how much they cooled it down. Liquid carbon dioxide only exists at high pressures. That means the solid left no liquid behind as it sublimed – thus the name dry ice.

Dry ice is in common use as the cheapest way to get temperatures well below freezing. Dry ice sublimes at −78.5°C (−109.3°F) which has a wide range of uses – including ice cream and fog machines. (Be careful with the fog – it has elevated CO2 levels and is dangerous without good ventilation.) Two of these uses are ones I encounter regularly in the lab.

The first use is for shipping biological samples. Dry ice keeps the samples preserved without risking leakage or flooding. However, all of that CO2 is slowing turning into a gas. If it is not properly vented, the package will explode. (One of the reasons dry ice is harder to get now is that people without common sense made homemade explosives with this method.) We hear of reports about once a year of another exploding package, though it is getting less common.

-80 Freezer

A normal -80 freezer

The other side is related. Typically, bacteria and cell lines are stored frozen around dry ice temperature (-80°C).

It’s so common that people will mention having a “minus eighty” and most scientists will immediately know what you are talking about. These freezers often hold years of work, the product of countless hours of painstaking labor. Normally, they have backup batteries and similar systems, but those only last so long.

During grad school, the power went out in my lab’s building on a summer day, so I went into the sweltering, pitch-black building with cryogenic gloves, a flashlight, and bucket of dry ice. I was frantically packing the freezer with dry ice to help keep it cool. That was a bizarre contrast between feeling like I was in a sauna while working with stuff cold enough to burn my skin…

Published in Group Writing
This post was promoted to the Main Feed by a Ricochet Editor at the recommendation of Ricochet members. Like this post? Want to comment? Join Ricochet’s community of conservatives and be part of the conversation. Join Ricochet for Free.

There are 18 comments.

Become a member to join the conversation. Or sign in if you're already a member.
  1. OmegaPaladin Moderator
    OmegaPaladin
    @OmegaPaladin

    This sublimating post is part of July 2019’s Group Writing series – Chill Out!

    Hopefully this double header will fill some spaces on the calendar.

    • #1
  2. Clifford A. Brown Member
    Clifford A. Brown
    @CliffordBrown

    Many thanks to OmegaPaladin for closing the month out strong. This is part of our July theme series, in which you are invited to tell us how to “Chill Out!”

    The August theme is open for your participation: “Raining Cats and Dogs.”

    • #2
  3. PHCheese Inactive
    PHCheese
    @PHCheese

    I used a CO2 freeze tunnel in the process of making breaded cheese sticks in my cheese business. CO2 is  heavier than air and we used special vents to keep it from building up in the process room. Didn’t want the employees any sleepier  than the already were.

    • #3
  4. DrewInWisconsin Member
    DrewInWisconsin
    @DrewInWisconsin

    PHCheese (View Comment):

    I used a CO2 freeze tunnel in the process of making breaded cheese sticks in my cheese business.

    Say what?! You have a cheese business?!

    Are we friends? Do you need friends? Does your cheese need friends?!

    • #4
  5. DrewInWisconsin Member
    DrewInWisconsin
    @DrewInWisconsin

    At the grocery store my family owned, we would frequently get meat shipments packed in dry ice.

    When I was a kid, I liked to take the dry ice and throw it in one of the back room sinks, where it would bubble and steam, and fog up the room.

    Oh, who am I kidding . . . I did that well into my twenties.

    • #5
  6. Buckpasser Member
    Buckpasser
    @Buckpasser

    Been shipping food using dry ice for twenty years.  When I used to say that the dry ice would last x number of hours because it sublimates people would have a puzzled look on their face.  I had to tell them it “melts”.

    • #6
  7. Danny Alexander Member
    Danny Alexander
    @DannyAlexander

    Slight CoC language warning…

    https://www.youtube.com/watch?v=pLYydILXw5k

    • #7
  8. SkipSul Inactive
    SkipSul
    @skipsul

    Our fridge died last December.  But that December here was a bit warmish, and while we shopped for a new one my wife bought some slabs of dry ice to stuff in there.  When we dragged the new refer in, and got it going, I had a lot of fun showing the kids what you could do with the stuff.  Put a slab in the kitchen sink and put apple slices on it, then timed how long it took them to freeze solid (about 5 minutes).  Froze other stuff too (was very safety conscious about this – I showed them how quickly the out layers of an apple would freeze, then warned them this was what frostbite was like).  Was good for a couple of hours of entertainment with them.

    • #8
  9. Douglas Pratt Coolidge
    Douglas Pratt
    @DouglasPratt

    Forgive the extreme nerd-ness, but do the packages with dry ice really explode, or just burst? An explosion is an event that produces a supersonic shock wave. Gunpowder does not explode, it deflagrates; it burns very rapidly and produces lots of pressure, heat and gas. I have a hard time picturing a chemical reaction involving sublimating CO-2 that would produce a supersonic shock wave. If there was one, my brothers and sisters in the amateur fireworks community would surely have found a way to put it to good use.

    • #9
  10. SecondBite Member
    SecondBite
    @SecondBite

    I heard a story recently of a cargo or mail pilot who passed out on the taxi-way because his aircraft had been loaded with more dry ice packages than the ventilation system could handle.

    Fortunately he realized he was passing out and was able to stop the plane before anything bad happened. No harm done……that time.

    • #10
  11. OmegaPaladin Moderator
    OmegaPaladin
    @OmegaPaladin

    Douglas Pratt (View Comment):

    Forgive the extreme nerd-ness, but do the packages with dry ice really explode, or just burst? An explosion is an event that produces a supersonic shock wave. Gunpowder does not explode, it deflagrates; it burns very rapidly and produces lots of pressure, heat and gas. I have a hard time picturing a chemical reaction involving sublimating CO-2 that would produce a supersonic shock wave. If there was one, my brothers and sisters in the amateur fireworks community would surely have found a way to put it to good use.

    It depends on the pressure and quality of the seal.  Catastrophic failure at high pressure is going to have a lot of energy.

    The problem is that this kind of explosion requires confinement and will produce high-velocity shrapnel

    • #11
  12. Basil Fawlty Member
    Basil Fawlty
    @BasilFawlty

    Let the punishment fit the rime.

    • #12
  13. Kim K. Inactive
    Kim K.
    @KimK

    My inlaws were making a trip to visit us (3 days on the road) and planned to bring along some specialty Dutch foodstuffs not available in the Mojave Desert. The day before leaving they bought some dry ice in which to pack the goodies and put it in their deep freeze. The next morning before leaving they went to get the dry ice and pack the delicacies but couldn’t find it in the freezer – it had vanished!

    • #13
  14. Basil Fawlty Member
    Basil Fawlty
    @BasilFawlty

    Kim K. (View Comment):

    My inlaws were making a trip to visit us (3 days on the road) and planned to bring along some specialty Dutch foodstuffs not available in the Mojave Desert. The day before leaving they bought some dry ice in which to pack the goodies and put it in their deep freeze. The next morning before leaving they went to get the dry ice and pack the delicacies but couldn’t find it in the freezer – it had vanished!

    The freezer?

    • #14
  15. Caryn Thatcher
    Caryn
    @Caryn

    DrewInWisconsin (View Comment):

    At the grocery store my family owned, we would frequently get meat shipments packed in dry ice.

    When I was a kid, I liked to take the dry ice and throw it in one of the back room sinks, where it would bubble and steam, and fog up the room.

    Oh, who am I kidding . . . I did that well into my twenties.

    Oh, heck, I still do it!  Not to the point of fogging up the room, but it’s still fun to watch the “smoke” curl up and over the sink.  Very Addams Family tea time.

    • #15
  16. DrewInWisconsin Member
    DrewInWisconsin
    @DrewInWisconsin

    Caryn (View Comment):

    DrewInWisconsin (View Comment):

    At the grocery store my family owned, we would frequently get meat shipments packed in dry ice.

    When I was a kid, I liked to take the dry ice and throw it in one of the back room sinks, where it would bubble and steam, and fog up the room.

    Oh, who am I kidding . . . I did that well into my twenties.

    Oh, heck, I still do it! Not to the point of fogging up the room, but it’s still fun to watch the “smoke” curl up and over the sink. Very Addams Family tea time.

    It never got really foggy, but yes, it was fun watching it “overflow” onto the floor.

    • #16
  17. Shauna Hunt Inactive
    Shauna Hunt
    @ShaunaHunt

    One of my family traditions was homemade root beer on Independence Day and Halloween. I remember the adults adding the dry ice and watching it bubble and “smoke”. Better yet was the homemade ice cream with the homemade root beer! That was some root beer float!

    • #17
  18. Randy Weivoda Moderator
    Randy Weivoda
    @RandyWeivoda

    DrewInWisconsin (View Comment):

    PHCheese (View Comment):

    I used a CO2 freeze tunnel in the process of making breaded cheese sticks in my cheese business.

    Say what?! You have a cheese business?!

    Are we friends? Do you need friends? Does your cheese need friends?!

    I’m afraid he retired from cheese-making years ago.

    • #18
Become a member to join the conversation. Or sign in if you're already a member.