Answer | Crossword Clue |
---|---|
GAS | Hydrogen or nitrogen. |
AMMONIA | Nitrogen-hydrogen compound |
GAS | Helium or hydrogen |
ELEMENT | Hydrogen or oxygen. |
GAS | Oxygen or hydrogen |
GAS | Hydrogen or helium |
GAS | Hydrogen or neon |
ELEMENT | Hydrogen or helium |
ELEMENT | Helium or hydrogen |
ATNO | 1 for hydrogen or 2 for helium: Abbr. |