Abstract
Dissolution of calcite crystal was studied in 0.010 M NaNO3 solution involving various concentration of humic acid (HA) at ambient temperature under Ar atmosphere. The ethcing profile of calcite surfaces was observed by Atomic Force Microscopy (AFM). The dissolution rates in 0.010 M NaNO3 solution with HA are larger than those without HA in the range of pH below 4.0; however, the dissolution rates in 0.010 M NaNO3 solution with HA are clearly smaller than those without HA in the range of pH above 5.0
