Answers

2014-09-15T16:24:03+08:00
For me it's the number 8 because of the octet rule.
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2014-09-16T11:17:27+08:00
TRY LOOKING AT THE ELECTRONIC CONFIGURATION OF THE ELEMENT, THE ELECTRONS IN THE HIGHEST MAIN ENERGY LEVEL OCCUPIED IS THE NUMBER OF VALENCE ELECTRONS. Example: 1s2 2s2 2p6 the valence electron is 8

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