Re: Is it this easy to live on Earth?

On Oct 5, 7:41 pm, Willie.Moo...@xxxxxxxxx wrote:
This will have been the 7th time I've said the same thing, and the 7th
time you have ignored it.

The work required to raise the pressure of a gas from one pressure to
another is given by;

W = n R T * ln(Pa/Pb)

Where n = moles
R = rydberg constant = 8.314
T = temperature (Kelvins)
ln( ) = natural logarithm function
Pa = the higher pressure
Pb = the lower pressure

The atmosphere of Mars is 0.13% oxygen by volume
and its atmospheric pressure is no less than 0.6 kpa

So the partial pressure of oxygen on Mars is 0.00078 kpa

The atmosphere of Earth is 21% oxygen by volume
and its atmospheric pressure is 101.3 kpa.

So the partial pressure of oxygen on Earth is 21.273 kpa

The ratio of these two pressures is 27,273

The logarithm of 27,273 is 10.2

The temperature on Mars averages 220 K

An adult male consumes no more than 909 grams of oxygen per day
Oxygen molecules are O2 - which total 32 atomic mass units. That
means that 1 mole of oxygen molecules equal 32 grams - this means that
909 grams is 28.4 moles

So, the amount of work needed to raise the pressure of 28.4 moles of
oxygen in the Mars atmosphere from 0.00078 kpa to 21.273 kpa is

W = 28.4 * 8.314 * 220 * 10.2 = 529,847.89 joules

Divide this by 86,400 seconds in 24 hours - and this obtains 6.1 watts
continuous.

Now, oxygen requires 0.92 joules per gram per K. Room temperature is
295 K - 75 K higher than 220 K. So, to raise 909 grams 75 K
requires an additional 62,721 joules. Again divided by 86,400
seconds in a day this averages out to 0.73 watts.

So, to raise oxygen pressure to breathable levels and heat it to room
temperature requires less than 7 watts per person.

A similar calculation regarding water vapor in both Earth's atmosphere
and Mars' atmosphere obtains a lesser figure - the sum of all figures
is less than 10 watts per person.

In that case, cooling off a toasty and robust atmosphere and otherwise
extracting or converting in order to obtain as much O2 as you'd like
is another no brainer of hardly any local energy demand, and this is
especially impressive since none of the required energy (no matters
how much) need be imported, and unlike Mars as having essentially
zilch worth of water, there's likely hundreds of teratonnes of easily
accessible water within them acidic clouds surrounding Venus, which
also means that Venus already has nitrogen and mineral salts to work
with.

We couldn't have done it without you.

~ Brad Guth Brad_Guth Brad.Guth BradGuth BG




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