Which halogen molecule, "X2," has the lowest dissociation energy?
Correct answer: C. I2
- A. Cl2
- B. Br2
- C. I2
- D. F2
Explanation
The correct answer is I2. Among the halogen molecules, iodine (I2) has the weakest bond due to its large atomic size, which leads to poorer orbital overlap and therefore the lowest bond dissociation energy. Although F2 has a small atomic size, it experiences electron-electron repulsion that weakens its bond; however, it is still stronger than I2. Cl2 and Br2 have relatively stronger bonds than I2 due to better orbital overlap, resulting in higher dissociation energies.
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About s-Block and p-Block Elements
The s and p blocks are studied through their valence-shell configurations, periodic trends and characteristic chemical properties. Work covers the reactions of Group I and Group II elements, the behaviour of Group IV elements, and how atomic size, ionization energy, electronegativity and metallic character change across periods and down groups.
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