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Explain why the electronegativity of oxygen is higher than that of sulfur, even though both are in the same group.

medium 2 marks Class 11 · Chemistry · Classification of Elements and Periodicity in Properties
Answer
Oxygen has a higher effective nuclear charge due to a smaller atomic size, resulting in a stronger attraction for bonding electrons, whereas sulfur’s larger radius reduces this attraction.

Step-by-step solution

  1. Both O and S belong to group 16.
  2. "O has atomic number 8 with 3 electron shells, S has atomic number 16 with 4 shells.
  3. "Because the valence electrons in O are closer to the nucleus, the effective nuclear charge is higher.
  4. "Higher effective nuclear charge increases electronegativity.
  5. "Thus O is more electronegative than S.
Common mistake: Assuming electronegativity depends only on group number

Concept tested: Electronegativity trend down a group

Published · How this solution was prepared and checked

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