Hi there, I have to solve this problem:(adsbygoogle = window.adsbygoogle || []).push({});

Use the following data to estimate the molarity of a saturated aqueous solution of ##Sr(IO_3)_2##

So, I think I should use the Van't Hoff equation in some way, but I don't know how.

I also have:

##\Delta_r G=\Delta G^o+RT\ln K##

##K## is the equilibrium constant, and ##\Delta G^o## is the Gibbs energy of formation.

In equilibrium ##\Delta_r G=0## and the equation can be managed to get the Van't Hoff equation, which is:

##\ln K_1-\ln K_2=-\displaystyle\frac{\Delta H^o}{R} \left( \displaystyle\frac{1}{T_2}-\displaystyle\frac{1}{T_1} \right)##

I think that I should handle this equations to get the equilibrium constant in some way, and then the molarity. Another equation that may be useful is the definition of the Gibbs energy:

##\Delta G^o=\Delta H^o-T\Delta S^o##

The chemical equation involved I think should be:

##Sr(IO_3)_2(s)+H_2O(l) \rightleftharpoons Sr^{2+}(aq)+2IO_3^{-}##

And from it: ##K'=\displaystyle\frac{[Sr^{2+}][IO_3^{-}]^2}{[Sr(IO_3)_2]}##

The solid concentration remains constant, and then: ##K=[Sr^{2+}][IO_3^{-}]^2##

Can anybody help me to work this out?

Thanks.

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# Homework Help: Estimate molarity from enthalpy, gibbs energy and entropy of formation

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