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Question
The given graph shows the trends in melting points of transition metals:
Explain the reason why Cr has the highest melting point and manganese (Mn) has a lower melting point.
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Solution
Chromium has the greatest number of unpaired electrons in its valence shell [Ar.3d54s1]. These unpaired electrons contribute to the creation of strong metallic bonds. As a result, the elements of the chromium group have extremely high melting points. Manganese has a half-filled d-orbital configuration, which means that all of its electrons spin in the same direction. Mn has a lower melting point because it has fewer interatomic forces of attraction, which are easier to break.
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