Chemistry
Five atoms are labelled V to Z
| Atoms | Mass Number | Atomic Number |
|---|---|---|
| V | 40 | 20 |
| W | 19 | 9 |
| X | 7 | 3 |
| Y | 16 | 8 |
| Z | 28 | 14 |
(i) Which one of these atoms has an electronic configuration 2, 7? (2) has an electronic configuration 2, 7 ?
(ii) Write down the formula of the compound formed by atoms X and Y.