Word eqation for the reaction between calcium carbonate and sulfuric acid?

CaCO3 is a base as it cant dissolve in water. if you do a simple experiment of dropping universal indicator solution onto chalk it will be green. this isnt because it is neutral but because UI solution is green to start with. you cant really talk about the pH of a insoluble base because you cant measure it easily. however it does neutralise acid so it is a base... but NOT an alkali. acid + base -> salt + water + carbon dioxide