When \( 200 \, \text{mL} \) of \( 0.2 \, \text{M} \) acetic acid is shaken with \( 0.6 \, \text{g} \) of wookd charcoal, the final concentration of acetic acid after adsorption is \( 0.1 \, \text{M} \). The mass of acetic acid adsorbed per gram of carbon is __________ \( \text{g} \).
