hw do we find whether a given element is a non metal if we know its electronic configuration?
At first write the electronic configuration of an element.
From atomic number 1 to 20 the element with 1-2 electrons in outermost shell is metal. Element with 3-4 electrons may be metal non-metal or metalloid. But the elements with 5-7 electrons in outer most shell is essentially non-metal.
After the atomic number 20 it is better to predict the group-number in which element belongs( that is in syllabus of higher classes) and also need to understand the position of metalloids in periodic table this will help you to tell the given element is metal or non metals
For your knowledge the list of non-metals in periodic table is : H, C, N, O, F, P, S, Cl, Se, Br, I, and Xe.
From atomic number 1 to 20 the element with 1-2 electrons in outermost shell is metal. Element with 3-4 electrons may be metal non-metal or metalloid. But the elements with 5-7 electrons in outer most shell is essentially non-metal.
After the atomic number 20 it is better to predict the group-number in which element belongs( that is in syllabus of higher classes) and also need to understand the position of metalloids in periodic table this will help you to tell the given element is metal or non metals
For your knowledge the list of non-metals in periodic table is : H, C, N, O, F, P, S, Cl, Se, Br, I, and Xe.