Chapter 3 Atoms and Elements 3.3 The Periodic Table Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 1 Groups and Periods On the periodic table • Elements are arranged according to similar properties • Groups contain elements with similar properties in vertical columns • Periods are horizontal rows of elements 2 Groups and Periods Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 3 Periodic Table Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 4 Group Numbers Group Numbers • Use the letter A for the representative elements (1A to 8A) and the letter B for the transition elements • Also use numbers 1-18 to the columns from left to right 5 Names of Some Representative Elements • Several groups of representative elements are known by common names. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 6 Alkali Metals Group 1A(1), the alkali metals, includes lithium, sodium, and potassium. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 7 Halogens Group 7A(17) the halogens, includes chlorine, bromine, and iodine. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 8 Learning Check Identify the element described by the following: A. Group 7A(17), Period 4 1) Br 2) Cl 3) Mn B. Group 2A(2), Period 3 1) beryllium 2) magnesium 3) boron C. Group 5A(15), Period 2 1) phosphorus 2) arsenic 3) nitrogen 9 Solution A. Group 7A, Period 4 1) Br B. Group 2A, Period 3 2) magnesium C. Group 5A(15), Period 2 3) nitrogen 10 Metals, Nonmetals, and Metalloids The heavy zigzag line separates metals and nonmetals. • Metals are located to the left. • Nonmetals are located to the right. • Metalloids are located along the heavy zigzag line between the metals and nonmetals. Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings 11 Properties of Metals, Nonmetals, and Metalloids Metals • Are shiny and ductile • Are good conductors of heat and electricity Nonmetals • Are dull, brittle, and poor conductors • Are good insulators Metalloids • Are better conductors than nonmetals, but not as good as metals • Are used as semiconductors and insulators 12 Comparing a Metal, Metalloid, and Nonmetal 13 Learning Check Identify each of the following elements as: 1) metal 2) nonmetal 3) metalloid A. sodium ____ B. chlorine ____ C. silicon ____ D. iron ____ E. carbon ____ 14 Solution Identify each of the following elements as: 1) metal 2) nonmetal 3) metalloid A. sodium metal B. chlorine nonmetal C. silicon metalloid D. iron metal E. carbon nonmetal 15 Learning Check Match the elements to the description: A. Metals in Group 4A(14) 1) Sn, Pb 2) C, Si 3) C, Si, Ge, Sn B. Nonmetals in Group 5A(15) 1) As, Sb, Bi 2) N, P 3) N, P, As, Sb C. Metalloids in Group 4A(14) 1) C, Si, Ge, 2) Si, Ge 3) Si, Ge, Sn, Pb 16 Solution Match the elements to the description: A. Metals in Group 4A(14) 1) Sn, Pb B. Nonmetals in Group 5A(15) 2) N, P C. Metalloids in Group 4A(14) 2) Si, Ge 17.