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प्रश्न
Write scientific reason.
Lithium and sodium are included in the same group in periodic table.
उत्तर
- Electronic configuration of lithium is (2, 1). Electronic configuration of sodium is (2, 8, 1).
- Both lithium and sodium have single electron in their outermost shell.
- Their valency is 1.
- In the periodic table, elements belonging to the same group have the same valency. Hence, lithium and sodium are included in the same group in periodic table.
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संबंधित प्रश्न
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State modern periodic law.
Fill in the following blank with suitable word:
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Fill in the following blank with suitable word:
Group 18 elements are called ...............
What is the significance of atomic number in the modern classification of elements? Explain with the help of an example.
Name the scientist who prepared modern periodic table.
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(a) all metals
(b) all non-metals
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(a) It has 18 horizontal rows known as periods.
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