1. The problem statement, all variables and given/known data An extract form my textbook: " In general, easily liquefiable gases( ie. with higher critical temperature) are readily adsorbed as van der walls forces are stronger near the critical temperature. Hence 1g of activated charcoal adsorbs more SO2( Tc=630K),than CH4 (Tc=190K) which is still more than 4.5 mL of H2(Tc=33K)." 2. Relevant equations 3. The attempt at a solution I'm having trouble understanding what this means. 1) Are we talking about VDW forces between the adsorbate( the gas) and the adsorbant? If so how are they stronger near Tc? 2) Are these gases liquefied and then adsorbed? Is this the general situation for adsorbtion of all gases? 3) What is the conclusion I'm supposed to draw from all this? Please do help.