Fill in the following blanks with suitable words:

(a) The basis for modern periodic table is………

(b) The horizontal rows in a periodic table are called……….

(c) Group 1 elements are called………

(d) Group 17 elements are known as………

(e) Group 18 elements are called…….

(f) According to Newlands’ classification of elements, the properties of sulphur are similar to those of oxygen because sulphur is the………. element starting from oxygen.