Neeraja Raghavan asked:
A glass jar is half filled with water. There is a live fish swimming in it. How can we boil the water that is inside the jar, without killing the fish?
Chris - I love that question. What is he doing? It’s basically fish bowl…
Dave - He’s apparently got a live fish swimming in the fish bowl and he wants to boil the water without harming the fish.
Chris - He wants to boil the water without harming the fish. Well, thinking about it. I mean, what we know about the boiling point of water. You can make water boil by raising the temperature that gives the water molecules more energy so they can escape from the body of water against the force being applied to the water surface by atmospheric pressure. You can also make water boil at the same temperature by reducing the pressure above the water. So, I suppose if you put the fish bowl into a very large space that he could evacuate very abruptly - so in other words, take all of the air out so the fish bowl is sitting in a vacuum, the water would boil without getting hot and therefore, wouldn’t harm the fish through heat. The problem is all the dissolved gases would presumably boil out instantly so the fish would asphyxiate very quickly unless you did it transiently, just quickly make it boil and then stop again. Just as a party trick to prove that this is possible.
Dave - I guess the other problem is if the water is boiling around the fish even if its not damaging the proteins because it’s not hot. the fish is probably going to get the bends because any water or gases...
Chris - Indeed because fishes have swim bladder, don’t they? This is how they regulate their buoyancies like a diver’s BCD, which makes them buoyant, neutral buoyancy in the water. So, if you had a fish that has a swim bladder, it could explode. I presume under those circumstances.
Dave - Even if you have a little shark or something which didn’t and then it’s gonna get the bends, so it’s probably not going to be a happy fish.
Kat - Horrible people.
Chris - But, it may not die straight away. So, there you go, there is the solution to your problem.
Neeraja Raghavan asked the Naked Scientists: Dear Naked Scientists: A glass jar is half filled with water. There is a live fish swimming in it. How can we boil the water that is inside the jar, without killing the fish? Regards, Neeraja. Dr Neeraja Raghavan What do you think? Neeraja Raghavan , Wed, 10th Jun 2009
Take the fish out! Don_1, Wed, 10th Jun 2009
Presumably you mean "boil SOME OF the water"?
Have you discovered some kind of super heat resistant fish species? Chemistry4me, Wed, 10th Jun 2009
Drop in a furuncle! Don_1, Wed, 10th Jun 2009
Boiling point depends on external pressure...
Compression and decompression would have to be done slowly otherwise the fish would die from “the bends”
A fish with a swim bladder would be in real trouble. Also, dropping the pressure until the water boiled would draw all the dissolved oxygen out of the water.
I'll go along with Don_1's answer. Madidus_Scientia, Wed, 10th Jun 2009
lightarrow, you are a clever lad!!!! lyner, Wed, 10th Jun 2009
I'm not getting into the debate on boiling fish alive just to check, so here's a related observation.
lightarrow, Thu, 11th Jun 2009
So it dies of anoxia rather than trauma. Bored chemist, Fri, 12th Jun 2009
Ok, what about steam distillation
Are you suggesting getting the fish pissed during the exercise?
You could use inert chemicals, like perfluoropentane:
That would spoil the taste! lyner, Sat, 13th Jun 2009
His arguement doesn't boil down to much in the end. Chemistry4me, Mon, 15th Jun 2009
Does Dr Neeraja Raghavan have a great secret he will be sharing with us some time? And why does he wish to boil some poor fish's life support system anyway? Don_1, Mon, 15th Jun 2009
Another solution of the problem could be this: take the fish and transfer it to another jar with water, than boil the water in the first one. lightarrow, Mon, 15th Jun 2009
Don already said that, first reply! Madidus_Scientia, Mon, 15th Jun 2009
Gulp! Haven't even seen it! lightarrow, Tue, 16th Jun 2009