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

Liquid water, initially at 25.00 °C & 1.000 bar is heated at constant

pressure to 95.00 °C, then is compressed at constant temperature to a final

pressure at which the volume is the same as the original volume (25.00 °C,

1.000 bar). Calculate the final pressure.

M = 18.015 g mole-1.

At 25.00 °C & 1.000 bar: ρ = 0.9970 g cm-3.

Data from text:

β = 2.04 x 10-4 K-1. κT = 45.9 x 10-6 bar-1.

2. Relevant equations

dV = (∂V/∂T)dT + (∂V/∂P)dP

β = (∂V/∂T)/V (Thermal Expansion)

κT = -(∂V/∂P)/V (Isothermal Compressibility)

3. The attempt at a solution

You rearrange the equation: dV = (∂V/∂T)dT + (∂V/∂P)dP and solve for the differentials by multiplying β and κT by the volume. The only problem is, I don't know how to get the volume. Should you assume dV ≈ 0 for liquids? The answer is 311.1 bars.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Thermodynamics: Calculating Final Pressure from Volume Differential

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**