Home Greenhouse

‘trap’

I’m not denying that greenhouse gases don’t trap radiation but no one says anywhere HOW they do.
Also what are the “greenhouse gases”? Is that just another way of saying CFCs?

I’m doing a science fair project, determining which greenhouse gas absorbs the most heat, and I need to get water vapor, methane, carbon dioxide, and nitrous oxide. I was wondering if i could buy like bottles of these types of gases, without harming myself or my family. I need to release the gases into 4 different mini-greenhouses, and i’m not sure if its possible. HELP?!! This think counts for 6 test grades!!