1. Chemistry
2. Inorganic Chemistry
3. The Periodic Table
4. Periodicity
5. 28111

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Electron affinity (E.A.) generally becomes more negative across a period, from left to right. However, the E.A. of phosphorus does not follow this trend and is less negative than that of silicon. Using orbital diagrams showing the valence electronic configuration of Si and P, explain why this exception occurs. Clearly justify your answer.