How can CO2 be an acid in solution???

Question

I am learning about acids and bases and the Bronsted-Lowry definition (grade 11)

Everything seemed to make sense until i found how that CO2 becomes an acid in water...
I don't understand how this can be, since acids donate protons to water... but where is the H+ in CO2???

To me it makes sense only that CO2 is a base because then it can accept an H+

Please show me the chemical equation/s of how CO2 reacts with water and how the proton gets transfered.

Answer 1

check out this link. its where my answer comes from.

http://en.wikipedia.org/wiki/Carbonic_acid
co2 undergoes other reactions when it gets into water and ends up taking hydrogens from water and using them to make a little carbonic acid. have you coverd equillibria yet in your chem class?

Answer 2

CO2 dissolved in water is an acid, but not by the definition of Bronsted-Lowry

it is an acid by the Lewis acid definition which says that an acid is an electron acceptor

the equation is
CO2 + H2O <==> H2CO3

essentially, the water donates a pair of electrons to the CO2 (the CO2 accepts the electron pair)

Answer 3

When something is "in solution" often this means it is in water (H2O). Thus: CO2 + H2O -> H2CO3 (carbonic acid).

Answer 4

CO2 + H2O ===> H+ + HCO3-