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Question
Write a scientific reason.
In group 2, beryllium and calcium elements, calcium is more electropositive element than beryllium.
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Solution
- Electronic configuration of beryllium is (2, 2).
The electronic configuration of calcium is (2, 8, 8, 2). - Among beryllium and calcium elements, calcium has the least effective nuclear charge exerting an attractive force on valence electrons.
- This is because of the electrons in the inner shells, which lie in between the valence shell and the nucleus.
- These electrons act as a shield, reducing the attractive force of the nucleus on the valence electrons. Therefore, calcium can lose its valence electrons more readily than beryllium.
Hence, in group 2, calcium is a more electropositive element than beryllium.
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