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The carbonic acid content of a water sample must be considered to determine the reagent requirements for the lime soda softening process. Given: pH=7.1 Total Alkalinity =203mg/L "as CaCO3 " Total Hardness =297mg/L "as CaCO3 " Calcium Hardness =235mg/L "as CaCO3 " Calculate the concentration of carbonic acid H2CO3 in moles per liter (i.e., M) using the data provided. Then enter the numerical value for your answer. Do not use scientific notation here, just type in the whole answer. As an example, if you get 510(4), enter 0.0005