Answer:
the atomic mass number for boron is 5
Explanation:
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Answer:
This means that the metal is more properly viewed as an array of positive ions surrounded by a “sea of mobile valence electrons.” Electrons which are capable of moving freely throughout the empty orbitals of the metallic crystal are called delocalized electrons (Figure below).
4Na +2e- ---->2Na2
O2 +2e- ------>2O
