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Periodic Classification of Elements — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10SciencePeriodic Classification of Elements2 Marks
Question
Explain why, the first period of the modern periodic table has only two elements whereas second period has eight elements.
✓

Answer

The 1st period has two elements because the 1st electron shell of an atom c a n take a maximum of two electrons only. The 2nd period of the periodic table has 8 electrons because the maximum no. of electrons which can be put in the 2nd shell of an atom is 8.

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