ELK Map gas is a mixture of various hydrocarbon, principally, methylacetylene and propadiene. Map gas is a mixture of various hydrocarbons, principally, methylacetylene and propadiene. It produces a relatively hot flame (2,976°C) with a high heat release in the primary flame (inner cone) (15,445kJ/m 3 ), less than for acetylene (18,890kJm 3 ) but much higher than for propane (10,433kJm 3 ). The ...