Question

what is periodicity? what is the cause of periodicity?​

Answer 1

Answer:

periodicity:the quality or character of being periodic; the tendency to recur at intervals.

Explanation:

Causes of periodicity : Similarity in the electronic configuration of valence shell of elements is the main cause of periodicity. Atomic number is the fundamental property of the elements. Similar elements are repeated at a regular interval When they arranged in the Increasing order of their atomic number.

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Answer 2

Periodicity :

"The repetition of Certain properties by the elements at a regular interval is known as periodicity".

Causes of periodicity :

Similarity in the electronic configuration of valence shell of elements is the main cause of periodicity.

Moseley pointed out that

1) Atomic number is the fundamental property of the elements.

2) Similar elements are repeated at a regular interval When they arranged in the Increasing order of their atomic number.

3) It has been found that atom have same number of electron in their valence shell have similar properties.

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