Question

if you are given 2 samples how do you distinguish which one is metal and which is non metal

Answer 1

By checking it's properties

Answer 2

It's quite simple

We know

Atomic no =no of proton=no of eletron

So by Atomic no we are able to identify no of elctron.

Simply arrange the electron in a shell .

If it gains electron from others then it is electronegative (Non Metal).

Similarly if it loses electron then it is electropositive (Metal).

All I want to say is Electropositive elements are metal whereas electronegative elements are non metal.