A. One gram (1.00 g) of activated charcoal was added to 100 ml. of the following acetic acid solutions and shaken until equilibrium has been established. The final concentrations were determined by titration with standardized NaOH solution. Calculate the surface area of charcoal given that the aren occupied by a single acetic acid molecule at the surface of charcoal is 21 A. [HAcl. /M 0.12 0.090 0.060 0.030 0.015 [HAcJnal /M 0.105 0.0765 0.0480 0.0220 0,0105 B. Under what conditions is the Langmuir adsorption isotherm valid? C. Explain why when charcoal was filtered after the adsorption process was complete, the first-20 m of the filtrate must be discarded.