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Question
The atomic number of an element 'X' is 11.
- Write the electronic configuration of X and find its valency.
- Write the formula and nature of its oxide.
Solution
(i) The electronic configuration of element X is : 2, 8, 1
Valency = 1
(ii) The formula of the oxide 'X' is X2O. It is because the valency of element 'X' is 1 and valency of oxygen is 2.
X2O is a basic oxide. Since, element X contains one electron in its valence shell, so it is a metal and metal forms basic oxides.
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-
1 18 a 2 13 14 15 16 17 b c d e
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| Symbol | Atomic No | Electronic Configuration | |
| 1. | He | 2 | ______ |
| 2. | Ne | ______ | 2,8 |
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| 4. | Na | 11 | ______ |
