Problem: A balloon filled with helium gas is found to take 6 hours to deflate to 50% of its original volume. How long will it take for an identical balloon filled with the same volume of hydrogen gas (instead of helium) to decrease its volume by 50%?

FREE Expert Solution
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FREE Expert Solution

Recall that Graham's Law of Effusion allows us to compare the rate of effusion of two gases. Graham's Law states that the rate of effusion of a gas is inversely proportional to its molar mass.


rate = 1MM


This means that when comparing two gases:


rate1 rate2 = MM2MM1


Since time is given:

Let's designate He as gas 1 and H2 as gas 2. Recall that rate = volume/time. This means:


rateHerateH2=VHetHeVH2tH2


Since the volume of He = volume of H2, the equation simplifies to:


rateHeratedisilane=VHetHeVH2tH2rateHerateH2=tH2tHe


Plugging this into Graham’s Law:

91% (287 ratings)
Problem Details

A balloon filled with helium gas is found to take 6 hours to deflate to 50% of its original volume. How long will it take for an identical balloon filled with the same volume of hydrogen gas (instead of helium) to decrease its volume by 50%?

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