Answer | Crossword Clue |
---|---|
HYDROGEN | Lightest known substance |
HYDROGEN | Lightest of all known substances. |
HYDROGEN | The lightest of all known substances. |
LITHIA | Oxide of the lightest known metal. |
METAL | Lithium is the lightest one known |
lithium | a soft silver-white element of the alkali metal group that is the lightest metal known and that is used especially in alloys and glass, in chemical synthesis, and in storage batteries see element table |