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Question
An element has an atomic number of 11 and its mass number is 23. What is the arrangement of electrons in the shells? State nuclear composition of an atom of the element.
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Solution
Given: Atomic no. = 11
Mass no. = 23,
Electronic configuration – (2, 8, 1)
| K | L | M |
| 2 | 8 | 1 |
Nuclear composition of an atom of the element is – 11 protons and 12 neutrons.
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