MAPP gas discontinuation

Live torch demonstration comparing C₃H₈ (propane) vs C₃H₄ (MAPP) — MAPP heats faster, steel reaches red heat first. Used to illustrate enthalpy-of-reaction effect on flame temperature. Side teaching: MAPP no longer manufactured (EPA closure of Chicago plant ~2011); plumbers now use propylene C₃H₆ in yellow cylinders.

This article goes through the combustion and the enthalpy of reaction and the fact that I have nitrogen in the air, which lowers the 3000 degrees centigrade temperature of acetylene. If I was talking about fuel gases like gasoline or aviation fuel, in pure oxygen it might burn at 2800 centigrade, but in air with four moles of nitrogen for every mole of oxygen, it's going to be burning at about 2000 degrees. And I can prove that to you right now, because I have some MAPP gas. They don't sell it anymore, but I have a number of bottles in my office.