Answer | Crossword Clue |
---|---|
BORON | Element discovered in 1812 |
NEON | Element discovered in 1898 |
EINSTEINIUM | Element discovered in 1952 |
RADIUM | Element discovered in 1898 |
ERBIUM | Element discovered in 1843 |
RADIUM | Metallic element discovered in 1902. |
IONIUM | Radioactive element discovered in 1907. |