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RJWills
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I meant to put Clapeyron equation, auto correct had other ideas...
The densities of ice and water are 0.917 g cmE-1 and 1.00 g cmE-1 respectively. The latent heat of fusion of ice is 333 J gE-1. Use this information to derive the slope dp/dT of the water-ice coexistence line in atm/K at 1 atm pressure at 273K
dp/dT= ΔH/TΔv = (Δv + pΔv)/ TΔv
And of course ρ = m/v
V ice = vI, v water = vW
VI=1/0.917 vW=1 ∴ Δv= -0.0905125
∴ dp/dT=2*(-0.0905125)/-273*0.0905125 = 0.007326 atm/K
However I think this is wrong because I've not used the latent heat of fusion. A suspicion is that I may be using the wrong formula, my lecturer didn't have very distinguishable u's and v's... Is the equation for change in enthalpy Δu+pΔv or Δv+pΔv. If the former is true (seems more likely) how do I use the lhf?
Thanks :)
Homework Statement
The densities of ice and water are 0.917 g cmE-1 and 1.00 g cmE-1 respectively. The latent heat of fusion of ice is 333 J gE-1. Use this information to derive the slope dp/dT of the water-ice coexistence line in atm/K at 1 atm pressure at 273K
Homework Equations
dp/dT= ΔH/TΔv = (Δv + pΔv)/ TΔv
And of course ρ = m/v
The Attempt at a Solution
V ice = vI, v water = vW
VI=1/0.917 vW=1 ∴ Δv= -0.0905125
∴ dp/dT=2*(-0.0905125)/-273*0.0905125 = 0.007326 atm/K
However I think this is wrong because I've not used the latent heat of fusion. A suspicion is that I may be using the wrong formula, my lecturer didn't have very distinguishable u's and v's... Is the equation for change in enthalpy Δu+pΔv or Δv+pΔv. If the former is true (seems more likely) how do I use the lhf?
Thanks :)