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Periodic Classification of Elements — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10SciencePeriodic Classification of Elements3 Marks
Question
What is Newlands’ law of octaves? Explain with an example.
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Answer

According to the Newlands’ law of octaves, when elements are arranged in the order of increasing atomic masses, the properties of the eighth element (starting from a given element) are a repetition of the properties of the first element.
For example:
If we start with lithium as the first element, we find that the eighth element from it is sodium having the similar properties to lithium.

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