How to Calculate q, w, Delta T, Delta U, and Delta H for Adiabatic Expansion?

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The discussion focuses on calculating thermodynamic properties during an adiabatic expansion of 6.0 mol of nitrogen (N2) gas. Key equations include q = 0 for adiabatic processes, ΔU = w, and the relationship T(final) = T(initial) * (V(i)/V(f))^(1/c). The confusion arises regarding the correct method to calculate work, with participants debating between using the constant pressure of 95 kPa or applying heat capacity methods. The final pressure of the gas is not fixed at 95 kPa, which adds complexity to the calculations.

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A sample of 6.0 mol N2 is originally confined in 30 dm^3( ie L) at 273K and then undergoes adiabatic expansion against a constant pressure of 95kpa until the volume has increased by a factor of 2.0. calculate q,w,delta T, Delta U and Delta H (The final pressure of the gas is not necessarily 95 kpa)

For this Q I know

q= 0 since the process is adiabatic

therfore delta U = w (work) = Cp (Heat Capacity constant Pressure) Delta T

Also I know

T(final) = T(initial) * (V(i)/V(f))^(1/c)


Should I use work = 95 *30 or should I use the heat capacity method...as these yield different results??

OR is there another method to solve the rest of the Q??...any hints/suggestions would be great!

cheers

rhys
 
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just out of curiosity, are you a UWA student doing CHEM2210 by any chance?
 

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