Collocations for gas - noun

deadly, noxious, poisonous, toxic
explosive, flammable, inflammable (esp. BrE), radioactive
compressed, hot
colourless/colorless, odourless/odorless
inert, noble
exhaust, greenhouse
pollution from greenhouse gases

hydrogen, methane
mustard, nerve, sarin, tear
Police used water cannon and tear gas against demonstrators.

laughing (= nitrous oxide)

emit, give off, produce, release
It gives off a poisonous gas as it decomposes.

build up
Noxious gases had built up in the sewer.

escape, leak
Toxic gases can escape through one of the pipes.

emissions
greenhouse gas emissions

chamber
Millions of Jews were sent to the gas chambers by the Nazis.

mask

butane (esp. BrE), coal, natural, propane (esp. BrE)
bottled, Calor™ (BrE), cooking (AmE)

cook with
I prefer to cook with gas.

light, turn on
I lit the gas and put the soup on to warm.

appliance, boiler (esp. BrE), central heating (BrE), cooker, fire, furnace (AmE), heater, lamp, oven, range (AmE), stove
bottle (BrE), canister, cylinder, pipeline
board (BrE)
exploration, industry
field, reserves
Chinese gas reserves are now being tapped.

supply
leak
All gas leaks should be reported as soon as possible.

gas mark 2, 3, etc. (BrE)
Set the oven at gas mark 4.

pedal
He hit the gas pedal and headed off.

station
We stopped at a gas station to fill up.