Chapter 19 Elements and Their Properties Section 1

Chapter 19 Elements and Their Properties Section 1 Metals

�Located on left side of Periodic Table �Ductile, malleable, good conductors of heat & electricity � 1 -3 valence electrons – tend to lose electrons �Form ionic bonds �Most solids at room temperature (except) �Most reflect light = shiny = luster Metals Review

�Like a pot luck dinner �Metallic bonding is the special type of bonding with positive ions surrounded by a cloud of electrons. �Outer level electrons are not held tightly to the nucleus �Electrons move freely among the positively charge metallic ions Metallic Bonding

�Ductile and malleable – metal doesn’t break because the ions are in layers that slide past each other without losing attraction to the electron cloud �Conduct electricity – outer level electrons weakly held and move freely Metallic Bonding Explains Metallic Properties

�Group 1 metals – 1 valence electron �Softer than most metals �MOST REACTIVE of all metals �React violently with oxygen and water �Must be stored in unreactive oils �Do NOT occur in nature as elements – always in compounds Alkali Metals

�Group �Very 2 metals – 2 valence electrons reactive metals �Do NOT occur in nature as elements – always in compounds Alkaline Earth Metals

�Groups 3 -12 are in transition between groups 1 -2 and 13 -18 � 1 -3 valence electrons �Most familiar metals because they occur as elements in nature �Often form colorful compounds Transition Elements

� Lanthanides # 58 -71 (follow lanthanum) � Actinides #90 -103 (follow actinium) all radioactive and unstable � Transuranium elements beyond uranium # 92 all synthetic, all radioactive Inner Transition Metals

Chapter 19 Elements and Their Properties Section 2 Nonmetals

�Located on right side of Periodic Table (except) �NOT ductile, NOT malleable �NOT good conductors of electricity and heat � 5 -7 valence electrons – tend to gain or share electrons. Form ionic or covalent bonds �Hydrogen can lose 1 or gain 1 electron �Most gases at room temperature �NOT shiny Nonmetals Review

�Group 17 � 7 valence electrons � 4 nonmetals, 1 metalloid �Fluorine is the MOST chemically active of all elements Halogens

�Group � 8 18 valence electrons (except) �Chemically �Exist �No stable as isolated atoms naturally occurring compounds The Noble Gases

Chapter 19 Elements and Their Properties Section 3 Mixed Groups

�Located in the middle of Periodic Table along the staircase � 3 -7 valence electrons �Can form ionic or covalent bonds �Metallic and nonmetallic properties Metalloids

� Allotropes are different forms of the same element with different molecular structures. � Diamonds – each carbon bonded to 4 other carbons in tetrahedrons. Tight crystalline structures � Graphite – each carbon bonded to 3 other carbons in hexagonal layers. 4 th electron of each carbon is loosely bonded to the next layer – layers slide past each other – pencils � Buckminsterfullerene – buckyball – carbons bonded in soccer ball shape – 1991 used to create nanotubes Allotropes of Carbon

�Synthetic elements are manmade elements. �All have 92+ protons except #43 and #61 �Created by smashing existing elements with particles. �New elements disintegrate to form other elements �Studying how these elements form and how they disintegrate, scientists learn more about the forces holding atoms together. Synthetic Elements