Is the sea saturated with calcium carbonate

To explore this problem further, we must first find out how to determine whether a solution is saturated, undersaturated, or supersaturated with a given 

In other words, we want a thermodynamic answer. Having just spent several chapters developing a method for determining which way a reaction will go, we should be able to put it to use here. The reaction could be written 

If this reaction goes to the right, the solution is undersaturated. If it goes to the left, the solution is supersaturated. All we need to do is to determine the molar Gibbs energy of the dissolved mineral and compare it to the molar Gibbs energy of the pure mineral, and the question is answered. 

But dissolution reactions that result in uncharged solutes such as H4Si04(a ) and H2C03(fl6 ) are unusual. Most solutes are ionized to some extent, that is, they break up into charged particles, called ions. In other words, we write the dissolution reaction not as in (10.1), but as 

Having now learned about the solubility product, please do not tack the sp subscript on to every equilibrium constant you calculate. There are equilibrium constants for many types of reactions. The solubility product is an equilibrium constant for a reaction having a solid mineral or compound on the left side and its constituent ions on the right. 

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