How many chemical reactions are possible regarding the formation of carbonic acid and the dissolving of calcite?


A. 23
B. 10
C. 2
[D.] 3

?

Doesn't this depend upon how these are broken down?

H2O + CO2 <--> H2CO3 <-->H^+ + HCO3^- <--> H^+ + CO3^2-

How many reactions is that? Is it one or three or six? Not a very good question in my mind; i.e., the question isn't very well defined.
And we can do on and on with
CO2 + H2O + CaCO3 --> Ca(HCO3)2 --> CaCO3 + CO2 + H2O.
Is that counted?

To determine the number of possible chemical reactions regarding the formation of carbonic acid and the dissolving of calcite, we need to analyze the equations involved. The formation of carbonic acid (H2CO3) can occur when carbon dioxide (CO2) dissolves in water (H2O). The dissolving of calcite (CaCO3) can be represented by the equation:

CaCO3 + H2O → Ca2+ + HCO3- + OH-

By considering the different ways the reactants can combine and the different possible products, we can identify three possible chemical reactions:

1. Disproportionation of carbonic acid:
H2CO3 → H+ + HCO3-

2. Formation of bicarbonate ions:
HCO3- + H2O → H2CO3 + OH-

3. Dissolution of calcite:
CaCO3 + H2O → Ca2+ + HCO3- + OH-

Therefore, the correct answer is [D.] 3.