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waters

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## Homework Statement

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.

## Homework Equations

dV = (∂V/∂T)dT + (∂V/∂P)dP

β = (∂V/∂T)/V (Thermal Expansion)

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

## 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.