uh, water splits into 1 Hydrogen atom and 2 Oxygen atoms when hit with electricity. Water also can be made into Rocket fuel
https://en.wikipedia.org/wiki/Water_splitting
Dihydrogen Monoxide, DHMO for short, splits into 2 hydrogen atoms and 1 oxygen atom.
But we knew what you meant.
Oh, and DHMO is more commonly known as “water”.