It states mathematically $ p=Kx $ where $x$ is mole fraction of dissolved gas and $p$ is partial pressure of the gas.
Dissolution of gases is exothermic, so with increase in temperature, solubility $x$ decreases.
But increase in temperature also means an increase in partial pressure $p$ which in turn means an increase in solubility $x$. Where am I going wrong?
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$\begingroup$ Temperature only affects pressure if you allow it to: by keeping volume constant. If your system has a freely moving piston holding the gas for example, then temperature will lead to a volume expansion, pressure remaining constant. $\endgroup$ – Vinícius Godim Mar 24 '18 at 3:38
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At a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.
If temperature changes, the Henry's law constant itself changes.
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$\begingroup$ But how does it change? As in what is the dependence of K and temperature? $\endgroup$ – Cowgirl Mar 23 '18 at 17:36
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$\begingroup$ @Cowgirl read the section "Temperature dependence of Henry's law constant" in the linked webpage $\endgroup$ – DavePhD Mar 23 '18 at 18:06
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$\begingroup$ Read also: !sciencedirect.com/science/article/pii/S1387380615002183. $\endgroup$ – Mathew Mahindaratne Mar 23 '18 at 18:30