Chemistry help: egg on a mountain.

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Hello, Im stuck on a question. I can come up with ideas but tying them together gets me stuck. Plus word problems always confuse me greatly. OK:

At the top of a mountain, an egg is heated in boiling water for 4 minutes and is found to be uncooked. Explain.

What I know is: On the mountain the atmospheric pressure is lower. This lower pressure results in increased volume. If the volume is greater, the water takes longer to boil... so the temperature isnt as high. Is that why the egg isnt cooked??? Due to these conditions it would take longer than 4 minutes to cook the egg. Is that even remotely correct or am I way off. PLEASE HELP!!!!
 

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  • #2
brewnog
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You're almost there.

You're right to say that the atmospheric pressure at the top of a mountain is lower. This directly results in the boiling temperature of water being lower. The simple way to think of it is that when you boil water, you're trying to turn it into a gas. If the surrounding pressure is low, it's easier for the water to turn from liquid to gas, so it boils at a lower temperature.

As a result, your boiling water will be at a lower temperature compared with at sea-level. It's heat which cooks your egg, not the fact that it's just in boiling water, so you'll have a runny egg! It's not really anything to do with the water taking longer to boil (although it's going to be pretty nippy up there!), it's just that the water does not boil at as high a temperature.


At the top of Mount Everest, for example, water boils at about 72 degrees Celcius. It's impossible to make a decent cup of tea up there.
 
  • #3
Gokul43201
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brewnog said:
At the top of Mount Everest, for example, water boils at about 72 degrees Celcius. It's impossible to make a decent cup of tea up there.
Not an Earl Grey maybe...but a Darjeeling ?
 
  • #4
brewnog
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Gokul43201 said:
Not an Earl Grey maybe...but a Darjeeling ?


Mm, I asked for that really...

Anyway, you'd think so, but no. A lot of mountaineer friends of mine have had to get used to drinking crap tea.
 
  • #5
DaveC426913
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Brewnog has your answer. This part:
m0286 said:
This lower pressure results in increased volume. If the volume is greater, the water takes longer to boil...
is a red herring.
 
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Thanks A Lot!

THANKS SOO MUCH
I got it now.. umm minus the tea brands conversation but yea lol. THANKS
 
  • #7
FredGarvin
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m0286 said:
THANKS SOO MUCH
I got it now.. umm minus the tea brands conversation but yea lol. THANKS
See if you can ever get a Brit to not talk about tea. It's impossible.
 
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NateTG
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brewnog said:
Anyway, you'd think so, but no. A lot of mountaineer friends of mine have had to get used to drinking crap tea.

What, no portable pressure cooker?
 
  • #9
brewnog
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NateTG said:
What, no portable pressure cooker?

Apparently not. I'm not really sure why. Perhaps once you pour it into a mug, it just keeps boiling off so fast that it's stewed too much by the time you can drink it! Or maybe it's just because they're too heavy to carry... I don't know! Anyway, most of them are capable of going for a few days without a good brew. That in itself is a mystery to be answered...
 

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