4 Origin of the Periodic Table There were “gaps” in his table, which led other scientists to discover new elements.Moseley devised the current periodic table which is based on ATOMIC NUMBER
5 The Current Periodic Table Periodic means “repeating” pattern.The periodic table groups similar elements together (think about sections in the grocery store).Grouping makes it easier to predict the properties of an element.
6 Periods Periods: horizontal rows of elements (7) Just as the number of protons changes as you move from left to right across the periodic table, so does the number of electrons.Remember that sentences are written in rows and end with a period.
8 Groups Groups: Vertical column of elements on the periodic table (18) Remember that group is spelled group and groups go up and down.Elements in the same group have the same number of valence electrons (electrons in the last shell).
9 Boardworks GCSE Additional Science: Chemistry Atomic StructureValence electronsResponsible for atomic bondingEqual to the last digit of the group numberHow many valence electrons in this atom? What group would it be in?9
10 GroupsValence electrons determine an element’s properties so all elements in the same group have similar properties.What makes them different then???
12 Families of ElementsThink of each element as a member of a family that is related to other elements nearby.Elements are classified as metals, nonmetals or metalloidsGroups are sometimes referred to as families
14 MetalsPhysical Properties: Shiny (luster), good conductors, high density, ductile (can be made into thin wires), malleable (can be hammered into thin sheets) and most are silverChemical Properties: Corrosion (wearing away because of a chemical reaction with water), reactivity (bond with other atoms)
17 NonmetalsPhysical Properties: No luster, not conductors, brittle, not ductile, low density, and many are gaseous (can be solids or liquids too though)Chemical Properties: Highly reactiveAll, except for hydrogen, are on the right hand side of the periodic table.
22 Periodic Trends Labeling Directions Label the number of valence electrons at the top of each groupColor the metals one color, the nonmetals one color and the metalloids another.
23 3. Label the following groups: Alkali MetalsAlkaline Earth MetalsTransition MetalsBoron GroupCarbon GroupNitrogen GroupOxygen GroupHalogens (only group with all 3 states of matter!)Noble GasesLanthanidesActinides
25 Types of Metals 1. Alkali Metals: very reactive 2. Alkaline-Earth Metals: form compounds that are found in our bodies (calcium and magnesium compounds)3. Transition Metals: the properties gradually change from being more similar to Group 2 to being more like Group 13 (Gold, Silver and Platinum)