Question

A 1500 liter chamber has 80% nitrogen + 20% Oxygen. If you replace the air with 100% Oxygen at 240, 300, 400 LPM when do you reach 95% and 99% Oxygen?

Answer 1

Given

Total volume = 1500 L

Intial Oxygen = 0.2 * 1500 L = 300 L of Oxygen

Intial Nitrogen = 0.8 * 1500 L = 1200 L of Nitrogen

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So when we need to reach 95 % oxygen

Final oxygen volume = 0.95 * 1500 = 1425 L of oxygen

so we need to replace 1425 - 300 = 1125 L of Nitrogen with oxygen

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if speed is 240 LPM

then time required = 1125 L / 240 L/min = 4.6875 min

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if speed is 300 LPM

then time required = 1125 L / 300 L/min = 3.75 min

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if speed is 400 LPM

then time required = 1125 L / 400 L/min = 2.8125 min

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So when we need to reach 99 % oxygen

Final oxygen volume = 0.99 * 1500 = 1485 L of oxygen

so we need to replace 1425 - 300 = 1185 L of Nitrogen with oxygen

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if speed is 240 LPM

then time required = 1185 L / 240 L/min = 4.9375 min

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if speed is 300 LPM

then time required = 1185 L / 300 L/min = 3.95 min

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if speed is 400 LPM

then time required = 1185 L / 400 L/min = 2.9625 min

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