The air on the other side of the barrier contains more helium because helium diffuses through the porous barrier more quickly than other gases in the air. At high temperatures, the rate of diffusion of gases increases due to the increased kinetic energy of the gas molecules. As a result, the helium molecules diffuse through the porous barrier more quickly than other gases in the air, such as nitrogen and oxygen. This leads to an enrichment of helium on the other side of the barrier, where the air has a higher concentration of helium compared to the original air at 1000 degrees Celsius.