Here is the answer for the three of them
<span>N20 = 16 e-
</span><span>SeCl2 =20
</span><span>PBr3 = 26
Remember that t</span><span>o find the valence electrons in an atom you need to identify what group the element is in. An element in group 1A has 1 valence electron. If the element is in group 2A, then it has two valence electrons.</span>
<span>These atoms are known as valence atoms.</span>
it's Lithium or Li
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Answer:
The symbol for an atom indicates the element via its usual two letter symbol, the mass number as a left superscript, the atomic number as a left subscript (sometimes omitted), and the charge as a right superscript.
Explanation:
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