| Answer | Crossword Clue |
|---|---|
| ONE | Atomic number of hydrogen |
| REACTIVE | Like atomic hydrogen |
| TEN | Number of hydrogen atoms in butane |
| TEN | Number of hydrogen atoms in a butane molecule |
| SEVEN | Atomic number of nitrogen |
| TWO | Atomic number of helium |
| TEN | Atomic number of neon |
| TIN | Its atomic number is half of fermium's |
| ISOTOPES | Forms of elements having same atomic number. |
| ATE | Homophone for the atomic number of oxygen |
| ISOTOPE | One of several elements, having the same atomic number. |
