Practice writing out equations for the dissociation equilibrium of carbonic acid components and water (review)
Please write the following exercises (A) and (B) on a piece of paper for each of you.
（A）Write a definition equation for the concentration of DIC in terms of the three components of the carbonic acid. Let that equation be (1).
The molar concentration of each component is noted as 【component】.
（B）
・Write down three reaction equations in which atmospheric carbon dioxide dissolves in seawater and dissociates to carbonate ions.
・Write down the reaction equation for the dissociation equilibrium of water.
・For each reaction (dissolution equilibrium and dissociation equilibrium), write down the mass action equation.
The partial pressure of carbon dioxide in the atmosphere is written as pCO2.
The constant of dissolution equilibrium is K0, and this is given by Equation (2).
The constant for the dissociation equilibrium (first step) of the carbonic acid component is K1, and this is given by Equation (3).
The dissociation equilibrium (second stage) constant for the carbonic acid component is K2, and this is given by Equation (4).
The constant for the dissociation equilibrium of water is Kw, and this is given by Equation (5).
①The component before dissociation is placed on the left side (original form) of the reaction equation, and the component after dissociation is placed on the right side (product form).
②The law of mass action is 【product of the concentration of the component in its product form】／【product of the concentration of the component in its original form】＝equilibrium constant