2 The Periodic Tableis a chart that organizes all the elements in a way that shows patterns – both similarities and differences among the elements.Elements are listed by increasing atomic number.
3 The horizontal rows are called periods. There are 7 periods. The vertical columns are called groups. There are 18 groups.Elements in the same group have similar chemical properties.
4 PeriodsEach period corresponds to the energy levels found outside an atoms nucleusThe period that an element is located in tells you what the highest energy level is that will contain electrons
5 PeriodsThe most energy levels found in an atom (currently) is seven which corresponds to the seven periods in the tableExamplePotassium (K) is located in period 4 and thus will have its valence electrons in the fourth energy level
6 Period 1Period 2Period 3Group 1Group 234518Period 7
7 Special Groups Group 1 elements are known as the alkali metals. Group 2 elements are known as the alkaline earth metals.Group 17 elements are called halogens.Group 18 elements are called noble gases.Groups 3-12 are called transition metals.The Lanthanides and Actinides are the excerpts at the bottom.
8 Group 1 – Alkali Metals Have only one e- in the valence shell Most reactive of all metals – reactivity increases as you go down the groupHydrogen is an exception!Has one valence electron but is classified as a non-metal
9 Group 2 – Alkaline Earth Metals Has two e- in valence shellBecome increasingly soluble with increase in temperature
10 Group 18 – Noble GasesGenerally are chemically inert meaning they do not react with other elementsThis is because they already have 8e- in their valence shell causing them to be stable(He only has 2 valence e-)Only He and Ne are truly inert – others will react in limited amounts under specific conditions
11 Group 17 – HalogensHalogen means “salt former” – form salts when reacting with a metalMost exist as diatomic molecules in gaseous stateEx. Cl2All are one e- short of a full valence shell causing them to be very reactiveAre non-metals
12 Transition and Rare Earth Metals Some of the rest of the elements in the periodic table fall under these two categoriesTransition metals are groups 3 – 12Rare earth (inner transition) metals are broken down further into actinides and lanthanides
13 Transition and Rare Earth Metals These are also called the inner transition elements and they belong here
14 Representative Elements Groups 1, 2 (s block) and (p block) are often called representative elements. They are sometimes labelled 1A, 2A, 3A, …8A
15 These elements are called the representative elements
18 There are 3 major sections of elements in the periodic table: MetalsNon-metalsMetalloidsMetals are located to the left of the “staircase line” and non-metals are to the right (except H). Metalloids border the line.
19 Properties of Metals Luster (shiny) Good conductors High density Physical PropertiesChemical Properties:Luster (shiny)Good conductorsHigh densityHigh melting pointMalleable/bendableSolid at room temperature (except Hg)Easily lose electronsCorrode easily (ex: rusting or tarnishing)Low electronegativity
20 Properties of Non-metals Physical Properties:DullPoor conductorBrittleNot malleableLow density and melting pointChemical Property:Tend to gain electronsHigh electronegativity
21 Properties of Metalloids Metalloids border the “staircase” and tend to have some properties of both metals and non-metals.solidscan lose or gain electronssemi-conductors of electricity (Conduct heat and electricity better than non metal but not as well as metalsShiny or dullMalleable