Hydrogen can be prepared in several different ways, but economically the most important processes involve removal of hydrogen from <answer>hydrocarbons</answer>. Commercial bulk hydrogen is usually produced by the steam reforming of natural gas. At high temperatures (1000–1400 K, 700–1100 °C or 1300–2000 °F), steam (water vapor) reacts with methane to yield carbon monoxide and H
2.
The most economical way to prepare hydrogen involves removing it from what?
hydrocarbons