AP Chemistryeasymcq1 pt
How many valence electrons does a phosphorus atom (Z = 15) have?
A.5
B.3
C.15
D.8
Explanation
Core Concept
Phosphorus is [Ne] 3s² 3p³, so its valence shell (n = 3) holds 2 + 3 = 5 electrons. Group 15 elements all have five valence electrons.
Correct Answer
A5
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