Potash is composed mainly of potassium caronate, K2CO3. If 1.000g of potash reacts with sulfuric acid to produce 145 mL of carbon dioxide gas at STP, what is the % of potassium carbonate in the marble sample? K2CO3(s) + H2SO4(aq) -(arrow) K2SO4(aq) + H2O(l) + CO(g)