hydrogen therapy , hydrogen generator , generator hydrogen , hydrogen , Hydrogen Inhalation Machine , hydrogen inhaler , h2 inhalator h2 inhalator , molecular hydrogen therapy , hho therapy , hydrogen breathing machine 1. Hydrogen is a chemical element, the first on the periodic table. 2. The usual elemental form of hydrogen is hydrogen gas. 3. It is a colorless, odorless, highly flammable lightest gas composed of diatomic molecules. 4. The smallest, lightest,...