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Question
An element ‘A’ has mass number 23 and atomic number 11. State the –
- no. of neutrons in its shell,
- electronic configuration of the element ‘A’.
Solution
Mass number A = n + p (atomic number)
A = n + Z
23 = n + 11
∴ n = 23 – 11 = 12
(1) Number of neutrons = 12
(2) e = p = 11
∴ Number of electrons e = 11
∴ Electron configuration of A = 2, 8, 1
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RELATED QUESTIONS
Complete the following table.
| Atomic number | Mass number | Number of Neutrons | Number of protons | Number of electrons | Name of the Atomic species |
| 9 | - | 10 | - | - | - |
| 16 | 32 | - | - | - | Sulphur |
| - | 24 | - | 12 | - | - |
| - | 2 | - | 1 | - | - |
| - | 1 | 0 | 1 | 0 | - |
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