"Water gas" is a mixture of CO and H2 created by the reaction of water and glowing carbon. It was also called "Producer Gas" in contrast with "Natural Gas" which is a mixture of CH4 and CO2.
There was a time when this reaction was used to create a combustible gas from coal, which could then be piped around a plant and used in lieu of natural gas.
FWIW, this is why they couldn't just pour water on the glowing carbon core of the Chernobyl reactor when it went runaway since the glowing graphite core would have converted the water to an explosive gas and made an even bigger mess.
FWIW2, glowing carbon is so reactive that it will even strip oxygen off of CO2 C + CO2 => 2CO
FWIW3, when the source of glowing carbon is wood, the gas produced is commonly called "wood gas." When you hear old-timers talking about how trucks were run on wood during WWII, this is what they were talking about. About twenty years back, TMEN had a series of articles on converting engines to run on wood gas.
What was happening was that water was being dripped on calcium carbide, thereby causing the generation of acetylene gas. It was the acetylene which was actually running the engine, not water.
FWIW, a catalyst is a substance which facilitates a reaction but is not consumed thereby. The calcium carbide was definitely being consumed in order for the engine to run, therefore it was a fuel, not a catalyst.
FWIW2, this is the principle by which miner's headlamps used to operate.
FWIW3, this was the product which Union Carbide was founded on.
FWIW4, once upon a time gas welders purchased calcium carbide and made their own acetylene on the spot, whereas today we purchase acetylene in cylinders as a compressed gas.
15.02 - Liberating Ozone from Water
15.04 - Dissociating Water with Fire
15.06 - Power of Dissociated Water
15.08 - Dissociating Water with X-Rays - Radiolysis
15.09 - Dissociating Water with Ultrasonic Vibration - Puharich
15.10 - Dissociating Water with Alternating Current - Puharich
15.11 - Dissociating Water with Vacuum
15.12 - Dissociating Water with Acoustic Cavitation
15.13 - Dissociating Water Acoustically - Liberation of Quantum Constituents
15.18 - Keelys Process for Liberating Ether from Water
15.21 - Water Dissociation Demonstration
15.22 - Water is Sensitive to Thought
15.23 - Water is Predominantly Diamagnetic
15.24 - Water is Sensitive to Biometeorological Effects
16.14 - Thermionic and gaseous state diodes
8.8 - Water Wave Model
Dissociating Water with Microwave
Figure 15.00a - Fujiwara Water Before Prayer
Figure 15.00b - Fujiwara Water After Prayer
Part 15 - Dissociating Water
SVP Cosmology Part 15 - Dissociating Water Acoustically