Question:

(a) Mendeleyev discovered that when elements are arranged in

Last updated: 7/11/2022

(a) Mendeleyev discovered that when elements are arranged in

(a) Mendeleyev discovered that when elements are arranged in order of increasing atomic weight, certain sets of properties recur periodically (b) Main-group elements are those in the columns 3A to 8A of the Periodic Table. (c) Nonmetals are found at the top of the Periodic Table, metalloids in the middle, and metals at the bottom. (d) Among the 118 known elements, there are approximately equal numbers of metals and nonmetals. (e) A horizontal row in the Periodic Table is called a group. (f) The Group 1A elements are called the "alkali metals."