Hardness of metals

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Hardness of metals:

The metals are generally hard. The hardness of metals is due to strong metallic bond present in them. More is the strength of metallic bond, harder is the metal. The strength of metallic bond depends upon the number of valence electrons and size of kernel. More is the number of valence electrons for delocalisation, stronger is the metallic bond. Similarly, smaller is the size of +ve Kernels, greater is the force of attraction for delocalised electrons and stronger is the bond. For examples, alkali metals due to the presence of only one electron in their valey shell and larger size of atom form weak metallic bond and thus are soft metals.

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