(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The question states "What mass can the balloon lift at sea level where the density of air is 1.22 kg / m^3"..

Extra information given are, use of ideal gas equation is needed,

which is pV = nRT

where p is pressure, V is volume, n is number of moles, R is constant (R = 0.082057 L atm K^-1 mol^-1) and T being temperature in Kelvin (297 Kelvin = 25 degrees Celcius)

The balloon has radius of 48m and it is perfect spherical..

Sea level is defined to be 1 atm and 25 degrees Celcius.

3. The attempt at a solution

I tried to rearrange the ideal gas equation so I can get volume in one side and the rest on the other. however, when I do that, number of moles, n, cannot be found.

When I tried to approach from other direction, using pressure = force / area,

Assuming the pressure inside the balloon and outside are equal,

force is found, then used newton's second law to find mass.

That did not turn out to be the answer...

Is there a step you see that is going wrong?

Lecturer told me that I need to make use of ideal gas equation... thats the key equation to solve this problem apprently...

but I'm not sure where to start...

does anybody see how to start other than the methods I used?

Thank you

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# Homework Help: Mass a helium balloon can overcome!

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