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timurjin [86]
3 years ago
15

PLEASE HELP ME I'LL GIVE BRAINLIEST

Chemistry
1 answer:
Allisa [31]3 years ago
4 0
OMG I DID THIS TEST WHAT HOME SHOOL R U DOING AND THE ANSWER IS THE 2ND ONE
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Answer: It will take 11.775 seconds.

Explanation: As a sphere with a diameter of 0.1 mm, the area of an alveolus is

A = 4.π.r²

r for an alveolus would be: r = 0.00005m or r = 5.10^{-5}m

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A = 3.14.10^{-8}m²

The concentration change is to be 90% of the final, so

c = 0.9.3.14.10^{-8}

c = 28.26.10^{-9}

The oxygen diffusivity is 2.4.10^{-9}m²/s, that means in 1 second 2.4.10^{-9} of oxygen spread in one alveolus area. So:

1 second = 2.4.10^{-9}m²

t seconds = 28.26.10^{-9}m²

t = \frac{28.26.10^{-9} }{2.4.10^{-9} }

t = 11.775s

For a concentration change at the center to be 90%, it will take 11.775s.

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