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RE: A More Detailed Response To @trumpman

in #science7 years ago (edited)

It's been a while now since I made calculations like that for far less interesting chemical processes, but I'm pretty sure that

78.75 ml which is roughly 0.657 kg (again using an online converter)

is not the case, unless this human combustion device has a built-in high-end air compressor in it.

On the other hand, my guess is that a sudden release of 157 kJ would be enough to burn the cat's hair. Let's say the chemical reaction takes 0.2 seconds to complete. That would be an equivalent of 785 kiloWatt released (157 kJ/0.2s). And since the energy should be very concentrated on a small volume of air before it dissipates through the room, assuming 157 kJ is correct, my guess is, that it would burn through the cat's hair.

Poor cat, though.

Also you converted kJ to calories and then used the resulting value of 37 to apply it to air. Calories are defined by the specific heat capacity of water. Specific heat capacity of air is approx. four times less than of water which would result in a temperature increase of about 150 K.

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The specific heat that I found for hair though was in calories, hence the conversion. Another problem with your assumption here is that you assume a rather static environment where the cat would feel all of the energy but as seen in the video the cat wouldn't be in the entire burn.

You may be correct that 78.75 ml of hydrogen isn't 0.657 kg (as I used an online converter and put in atmospheric pressure for the pressure and 300 kelvin for the temp) but I may have done something wrong (again 2 AM calculations)

While I definitely agree my calculations are certainly flawed somewhere (chemistry is honestly one of my least liked subjects) I will definitely say that if you can find flaws in this than write a post debunking my post and correct the answer and you will get some pretty hefty votes from everyone! I apologize if my correction at the top is condescending, I have difficulty with tone. But we also have to keep in mind that this, by no means, is taking account the amount of burn or the fact that most farts are released over a period of time and usually aren't instant.

Ah, now I understand. (It didn't sound condescending, btw. I hope I didn't either). I still think you would have to give more weight to the spec. heat capacity of air because it is the transmitter of energy until it reaches the cat skin.

The conversion of hydrogen volume to the amount of hydrogen goes through the molar volume of an ideal gas which is under normal conditions 22.4 liter/mol. (0.0785 liter / 22.4 liter/mol) would give us 0.00325 mols of hydrogen. Maybe the converter you used was working with cube meters or something?

Nah, I am not going to make a post :-) Chemistry and physics are way too far back for me.

Now, I am thinking that this guy might have sucked in some lighter gas into his rectum. Some people can fart at will.

No you didn't sound condescending, sorry for the late reply. School just started up along with some other things.

If there are 0.00325 mols of hydrogen as stated then the energy released by the hydrogen would be 1.57 kJ instead of 157 kJ thus reducing the temperature even more. I do apologize if my conversions are incorrect and will make the note.

Please turn that into a more comprehensive post

Alright guys... Challenge accepted.

Please take the challenge seriously and don't dissapoint us!