Relation between temperature and boiling point?

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The discussion addresses the relationship between the latent heat of vaporization, temperature, and boiling point of a substance. It clarifies that while both latent heat and entropy change depend on temperature, the boiling point is primarily influenced by external pressure. The Gibbs energy equation indicates that the boiling point can be expressed in terms of latent heat and entropy change, leading to confusion about temperature dependence. It is emphasized that boiling occurs when the equilibrium vapor pressure matches the external pressure, reinforcing that boiling point is not solely a temperature-dependent quantity. Understanding this relationship is crucial for interpreting phase changes in substances.
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Hello,

I am encountering some confusion with the relation between the latent heat of vaporization and the temperature of a substance. I understand both the latent heat and the entropy change of vaporization are dependent on the temperature, assuming the pressure is held constant. However given that the change in Gibbs energy for a phase change is equal to zero, one can express the boiling point of a substance in the latent heat and entropy change: $$ \Delta g = l_{23} - T_{boil} s_{23} = 0$$ $$T_{boil} = \frac {l_{23}}{s_{23}}$$ Here 2 and 3 refer to the fluid and gas states of the substance respectively. Doesnt this imply that the boiling point of a substance is dependent on the temperature? How can I interpret this? I always thought of the boiling point as a quantity dependent on the outside pressure.

Thanks!
 
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You are aware that there is a one-to-one relationship between the temperature and the equilibrium vapor pressure, correct? And that boiling occurs when the equilibrium vapor pressure is equal to the outside pressure, correct?
 
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