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What is the valency of chromium?Does it vary and how ?Why there is a difference in the electronic configuration? |
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Answer» The actual electron configurations are:Cr = [Ar] 4s13d5 Cr = [Ar] 4s23d4The unexpected electron configuration of chromium (together with molybdenum) 3d54s1, rather than 3d44s2, emphasizes that the 3d and 4s levels are very close in energy and that alternative electron arrangement can differ only very slightly in energy. When the 3d and 4s levels are sufficiently close, the repulsion between the two electrons in the 4s orbital can cause one of them to move into a 3d orbital. So does it have valencies +3 and +2 ?Does this depend on its state at the time of reaction? If no then what causes its variation? |
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