Consider the following equilibrium:
H2CO3(aq) + H2O(l) H3O+(aq) + HCO3-1(aq).

What is the correct equilibrium expression?
a.)Ka=[H 3 O + ][HCO 1− 3 ] [H 2 CO 3 ]
b.) Ka=[H 3 O + ][H 2 CO 3 ] [HCO 1− 3 ]
c.) Ka=[H 2 CO 3 ][H 2 O] [H 3 O + ][HCO 1− 3 ]
d.) Ka=[H 3 O + ][HCO 1− 3 ] [H 2 CO 3 ][H 2 O]

Question

Consider the following equilibrium:
H2CO3(aq) + H2O(l)  H3O+(aq) + HCO3-1(aq).

What is the correct equilibrium expression?
a.)Ka=[H 3 O + ][HCO 1− 3 ] [H 2 CO 3 ]   
b.) Ka=[H 3 O + ][H 2 CO 3 ] [HCO 1− 3 ]   
c.) Ka=[H 2 CO 3 ][H 2 O] [H 3 O + ][HCO 1− 3 ]   
d.) Ka=[H 3 O + ][HCO 1− 3 ] [H 2 CO 3 ][H 2 O]

anonymous · Answer

In general, for the rea$$\color{green}{aA + bB \rightleftharpoons cC + dD}$$ction:
The equilibrium law expression is:$$\color{green}{K = \dfrac{[C]^c [D]^d}{[A]^a [B]^b}}$$
Don't include solids and liquids, just gases and aqueous solutions.