At 400 k both compounds are gases. At this temperature, which compound, ch4(g).

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

your answer would be “dry”

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.