Question

why we can not classify metal or non metal on the basis of thier physical properties

Answer 1

because there are similarities between metals and non metals if we compare them on the basis of their physical properties
..for example if you take money then you should know that he is a metal but we have studied the properties of metals that they are solids at room temperature but you have seen that mercury is liquid at room temperature so its contradict the physical properties so they are not exactly valid but they are ok.........

one more example is there like you know that you have study the properties of nonmetals that they are mostly liquids or gases at room temperature but we have a non metal that is bromine which is solid at room temperature should it also contradict the physical properties
so this these are the proofs why we don't consider physical properties of metals and nonmetals to compare them because there are some exceptions....

Answer 2

if answer is use full for you please mark on the brainlist answer. please