Solids - Solid-liquid equilibrium in binary mixtures
4 important questions on Solids - Solid-liquid equilibrium in binary mixtures
When one of two species is rather dilute and behaves as a solute, what can be assumed of the system?
How can an expression for enthalpy be derived when
is not constant with changing T?
Assuming the heat capacities for both phases are constant:
Given:![](data:image/png;base64,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)
How is an expression for x derived?
Substituting expression 3 in 2 and integrating:
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
Why does freezing of a binary mixture happen at a range of Tm and not at one temperature as with a pure compound?
Considering a metastable supercooled system:
By formation of ice the overall Gibbs free energy is lowered.
With the formation of ice the mole fraction of water is the solution is lowered. Which leads to a lower chemical potential of the liquid phase. Ice is formed until the chemical potential of the solution becomes the same as that of the ice.
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
![Trustpilot Logo](/images/design_2020/lp/clp-trustpilot-en.png)