Isn't jaka more for qualitative questions? Would ile work here, or is it only for countable quantification?
In (UK) English I'd ask:
"How hot is this gas?" if an approximate answer (e.g. Cold Room temperature Warm Hot) is sufficient;
"What is the temperature of this gas?" if I wanted an answer to the nearest °C.
98.6 F / 37 C
Ten gaz ma silny zapach.
Ten gaz jest oddechem!
"This gas is a breath"?
Almost. But in (UK) English I think "breath" has to be qualified, e.g.:
"This gas is one breath" - This gas is exactly one lungful of air.
"This gas is Einstein's final breath".
"This gas is human breath".