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Question
Make a chart which shows the name of the element, valency, atomic number, electronic configuration in the 2nd row of the modern periodic table and arrange these elements in ascending order of atomic mass.
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Solution
| Elements of 2nd row of modern periodic table | ||||||||
| Name | Lithium | Beryllium | Boron | Carbon | Nitrogen | Oxygen | Fluorine | Neon |
| Valency | 1 | 2 | 3 | 4 | 3 | 2 | 1 | 0 |
| Atomic number | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
|
Electronic |
2, 1 | 2, 2 | 2, 3 | 2, 4 | 2, 5 | 2, 6 | 2, 7 | 2, 8 |
Elements in ascending order of atomic mass:
Lithium < Beryllium < Boron < Carbon < Nitrogen < Oxygen < Fluorine < Neon
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