AP Chemistryhardmcq1 pt
A PES spectrum shows two peaks of equal height. Which element could produce this spectrum?
A.Be (1s² 2s²)
B.Li (1s² 2s¹)
C.B (1s² 2s² 2p¹)
D.Ne (1s² 2s² 2p⁶)
Explanation
Core Concept
Beryllium has two occupied subshells, each holding two electrons, so its PES shows two peaks of equal height at 1s and 2s. Peak height tracks electron count directly.
Correct Answer
ABe (1s² 2s²)
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