hello :tongue2: i wanna ask about the deviation of real gases under low temperature and high pressure. :tongue: my reference book states that carbon dioxide deviates more than nitrogen and hydrogen,this is because the order of boiling points of is decreasing from carbon dioxide to hydrogen.this is because carbon dioxide liquefies at a much higher temperature than nitrogen and hydrogen. can anyone tell me what is the relationship between the ease of liquefaction and the deviation? anyway ,what is the meaning of liquefaction?is it something to do with it's boiling point??