How does rain dissolve limestone?

I understand that carbonic acid dissovles calcium carbonate. What I don’t understand is how. I tried google and got lots of info about acid/base reactions, but nothing that shows the chemical equation (process?) for how carbonic acid dissolves limestone.

A quick search turns up this:

I bow to your google skills. I spent about an hour trying to find that info. Thanks!

I’m not trying to denigrate your Google skills, but an hour? Really? What were you entering as search terms? I’m honestly curious, because entering “calcium carbonate carbonic acid reaction” gets me to the Wikipedia page on calcium carbonate as the second link, which contains this:

Calcium carbonate will react with water that is saturated with carbon dioxide to form the soluble calcium bicarbonate.

CaCO3 + CO2 + H2O → Ca(HCO3)2

I don’t have my search history, but I tried phrases like “How are caves formed”, “Acid base reactions”, “Limestone”, “Calcium Carbonate”, “Calcium Oxide”, “Carbonic acid” and others. I never thought about putting the two chemicals in the same search term. Seems like the obvious thing to do now that someone has pointed it out.:smack:

Which search engine do you use? I was trying to find the name of the style of dog brush I have been suggesting on Yahoo Answers. I use GoodSearch which gives a pittance to an assistance dog school for every search. It is Yahoo based. It returned several of my Yahoo answers. Bet Google wouldn’t.

I use Google.

I am thinking Google is less likely to turn up a Yahoo Answers thread than a Yahoo based search engine.

Nah, Google loves Yahoo Answers (which is sometimes bad, given how crazy some of the Answers that site gives can be).