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Question
Show diagrammatically the electron distributions in a sodium atom and a sodium ion and also give their atomic number.
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Solution
11Na -2,8,1 (11 electrons)
Na – 1e–—> Na+ (10 electrons) Electronic configuration 2, 8.
The atomic number of an element is equal to the number of protons in its atom. Since, sodium atom and sodium ion contain the same number of protons, therefore, the atomic number of both is 11.
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| Column A | Column B | ||
| 1. | Mass of proton | a. | +1 |
| 2. | Mass of electron | b. | -1 |
| 3. | Charge of electron | c. | 9.31 x 10-28g |
| 4. | Charge of proton | d. | 1.67 x 10-24g |
