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Question Question 4(1994)
Copy and complete the following table relating to the atomic structure of some elements :
| Element | Atomic No. | Mass No. | No. of Protons | No. of Neutrons | No. of Electrons |
|---|---|---|---|---|---|
| Beryllium | 4 | 9 | |||
| Fluorine | 9 | 10 | |||
| Sodium | 12 | 11 | |||
| Aluminium | 27 | 13 | |||
| Phosphorus | 31 | 15 |
| Element | Atomic No. | Mass No. | No. of Protons | No. of Neutrons | No. of Electrons |
|---|---|---|---|---|---|
| Beryllium | 4 | 9 | 4 | 5 | 4 |
| Fluorine | 9 | 19 | 9 | 10 | 9 |
| Sodium | 11 | 23 | 11 | 12 | 11 |
| Aluminium | 13 | 27 | 13 | 14 | 13 |
| Phosphorus | 15 | 31 | 15 | 16 | 15 |