Organization of the Periodic Table Mr. Shields Regents Chemistry U08 L02

Periodic Table - 1-92 are naturally occurring The periodic table has 115 natural and man made elements - 1 through 118 - 1-92 are naturally occurring - 23 are man made - 113, 115, 117 not yet produced - 112 of 115 are named (112=Copernicium Cn) - Everything above 83 is radioactive - Through 112: 2 liquids, 11 gases, 99 solids - 86 of the 112 named elements (78%) are metals!

The Gases At STP we know there are 11 gases and 2 liquids - 6 Noble gases - These gases are all monoatomic - He, Ne, Ar, Kr, Xe, Rn - 5 other elements are gases - These gases are always diatomic - H2, N2, O2, F2 and Cl2 - Mercury and Bromine are liquids

Periodic Table Elements that have similar chemical properties are aligned in COLUMNS called GROUPS The periodic table also organizes the elements in ROWS called PERIODS - There are 18 groups and 7 periods - Groups are numbered 1-18 - Periods are numbered 1-7 - corresponds to principle energy levels

Column numbering (1  18) is from left to right Period numbering (1  7) goes from top to bottom

The Inner Transition Elements Look at the bottom of the periodic table: Notice the group of elements known as the Lanthanides And Actinides are separated From the main periodic table. This is done strictly to help organize the periodic table. - Table would be too large if we included them Lanthanides/Actinides fit into period 6 & 7 - These two groups are known collectively as the INNER TRANSITION ELEMENTS

to help Reduce Table size Lanthanides Actinides These groups of elements Actually belong here Pulled to the bottom to help Reduce Table size

Periodic Table Columns - Numbering of Columns from 1 – 18 is new since mid 1980’s Tall columns on left and right originally numbered IA-VIIIA These are the current Groups 1,2, 13-18 Known as the REPRESENTATIVE OR MAIN GROUPS Short columns in middle were originally numbered IB-VIIIB Corresponds to Current Croups 3 – 12 These are known as the TRANSITION METALS Let’s see what this looks like…

Representative or Main Group Transition Elements Representative or Main Group 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

PERIODS The rows of the periodic table are called PERIODS - Presently there are 7 The length of each period grows in size as we go from Period 1 to 7 - Period 1 2 elements - Period 2&3 8 elements - Period 4&5 18 elements - Period 6 32 elements - Period 7 25 (up to element 111) The change has To do with the Filling of the s,p,d,f sublevels

Periods The periods of the periodic table represent the Number of principle energy levels contained by the atoms in that row. For example, K has electrons In the 4th Principle Energy level: K = 2-8-8-1

Blocks As we’ve discussed before, electrons fill orbitals in specific sublevels. This leads to Sections of the the periodic table being designated as “Blocks” based on what sublevel is being filled.

Some Characteristics of Blocks S Block: - Elements in group 1-2 are very reactive metals - Group 1 metals are so reactive they are never found free in nature D Block: - Transition metal compounds are very colorful - Copper compounds tends to form blues - Chrome compounds tend to form yellows P Block: - Contains a mix of metals, metalloids, and non-metals F Block: - All of the Actinides metals are radioactive

Common Family Names Recall that the vertical columns of elements are called Groups. They are also known as families because the elements In any given column have similar chemical Properties Elements forming a Family have specific Common names. The Smiths

Common Family Names Group # Family Names Transition Metals Family Names 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Group #

We’ve discussed how the periodic table is organized by: Atomic number Groups and periods Family names Block names based on which sublevels are filling The representative or main group elements vs transition & inner transition elements And lastly, the periodic table is also organized by 6) CLASSIFICATION of the elements

Classification by element type: By far ….Metals are the majority (abt 80%) 85 7 6 12

Properties of Metals & Non-Metals LUSTER HIGH LOW (or None) DEFORMABILITY Malleable & Ductile Brittle CONDUCTIVITY OF HEAT AND ELECTRICITY Good to Excellent Poor or Non-Conductor PHASE at STP Solid (except Hg) Gas or Solid (except Br) Ion FORMATION Loses e- to form positive ions Gains e- to form negative ions IONIZATION ENERGY Low (lowest is Fr) High (noble gases are the highest ELECTRONEGATIVITY High (highest is F)