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Question
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
4Be, 6C, 8O, 5B, 13Al Which is the most electropositive element among these?
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Solution
4Be, 6C, 8O, 5B, 13Al
Electronic configuration of the following elements is:
4Be = 2,2
6C = 2,4
8O = 2,6
5B = 2,3
13Al = 2,8,3
13Al is the most electropositive element among these because 4Be, 6C, 8O, 5B belong to same period, but 13Al belong to next period. According to the trend, electropositive character of an elements increases as we move from top to bottom in a group of the periodic table. This happens as the tendency of an atom to lose electrons increases due to decrease in nuclear charge and increase in numbers of shell.
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