Why does Cr have a higher melting point than Mn?
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Solution and Explanation
Answer: Chromium (Cr, configuration 3d54s1) has six unpaired electrons, all of which can take part in metallic bonding, so its metallic bonds are very strong and its melting point is high. Manganese (Mn, configuration 3d54s2) has its two 4s electrons paired, so fewer electrons are effectively available for strong bonding. Because Cr has more electrons involved in metallic bonding than Mn, Cr has the higher melting point.
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