What is the mass of the helium present - Thermodynamics

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To determine the mass of helium present, the ideal gas behavior is utilized along with the work done by the gas. The work done is expressed as dW = PdV, and under constant pressure, it simplifies to dW = nRdT. By integrating this expression from the initial to final temperature, the total work done can be calculated. The number of moles of helium can then be converted to mass using the molar mass of helium. This approach effectively combines thermodynamic principles to find the mass of the helium sample.
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A sample of helium behaves as an ideal gas as energy is added by heat at constant pressure from 273 K to 383 K. If the gas does 23.0 J of work, what is the mass of helium present?

I tried this and think u use m=Q/c*change in T, but not sure where to go from there
 
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The expression for the work done by the gas is:
dW=PdV
Since there is constan pressure we can write:
V=\frac{nRT}{P}
dV=\frac{nR}{P}dT
So
dW=nRdT
and
[/tex]W=\int_{T_1}^{T_2}nRdT[/tex]
Do the integral, use the molar mass of He to convert the # of moles of He to the mass, and then solve for the mass.
 
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