What are the differences between metals and non-metals?

Metals and non-metals are elements, apart from noble gases, that are generally presented in the periodic table of elements. There are a number of differences between the two classes. At the atomic level, metals have lesser number if valence electrons and find it much easier to donate electrons. Non-metals, on the other hand, have many more valence electrons and find it much easier to accept electrons. Metals are solid at room temperature (except mercury), while non-metals can be solid, liquid or gas at room temperature. Metals and non-metals can also be differentiated on the basis of malleability and ductility. Metals exhibit both, along with electrical conductivity; all these properties are absent from non-metals. Metals are shiny in appearance, whereas non-metals generally have a dull appearance.

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