Write the atomic number of the element present in the third and seventeenth group of the periodic table.

Write the atomic number of the element present in the third and sevent

1.	Write the atomic number of the element present in the third and seventeenth group of the periodic table.
Answer» Solution :Since it belongs to 3RD period, it will have outermost shell , n = 3. It.s configuration will be `3s^(2)3p^(5)`. `:.{:(He,Ne,Ar),(2,10,18):}` ` :. ` atomic number `(Z = 10 + 2 + 5) = 17` ` :. ` element Cl (Chlorine)