THE PERIODIC TABLE

THE PERIODIC TABLE

1. ISOTOPES

   • - TWO OR MORE ATOMS WITH THE SAME ATOMIC NUMBER BUT DIFFERENT MASS NUMBERS OR NUMBER OF NEUTRONS. ISOTOPES ARE SEPARATED THROUGH MASS SPECTROMETRY.
   • COMMON ISOTOPES
     • CARBON-14
       • IODINE-131
         • URANIUM-238
           • USED TO DETERMINE THE AGE OF SEDIMENTS FROM MARINE ENVIRONMENTS
         • TECNITIUM-99
           • COBALT-57
             • USED IN DIAGNOSIS OF PERNICIOUS ANEMIA
           • USED FOR X-RAYS OF SPECIFIC ORGANS FOR DIAGNOSIS AND TREATMENTS
         • TAKEN ORALLY TO TREAT THYROID CANCER
       • USED IN CARBON DATING OF ARCHAELOGICAL MATERIALS

2. CLASSIFICATIONS

   • GROUPS
     • GROUP 1
       • GROUP 2
         • GROUP 3
           • GROUP 4
             • GROUP 5
               • GROUP 6
     • GROUP 7
       • GROUP 8
         • GROUP 9
           • GROUP 10
             • GROUP 11
               • GROUP 12
     • GROUP 13
       • GROUP 14
         • GROUP 15
           • GROUP 16
             • GROUP 17
               • GROUP 18
   • PERIODS
     • FIRST
       • SECOND
         • THIRD
           • FOURTH
     • FIFTH
       • SIXTH
         • SEVENTH
           • EIGHTH
   • BLOCKS
     • S-BLOCKS
     • P-BLOCKS
     • D-BLOCKS
     • F-BLOCKS
     • G-BLOCKS

3. HISTORY

   • 1700S
     • 30 ELEMENTS WERE KNOWN TO MAN
   • 1800S
     • DOBEREINER, CLASSIFIED ELEMENTS BASED ON PROPERTIES INTO TRIADS
   • 1865
     • NEWLANDS , CLASSIFIED ELEMENTS BASED BY THEIR MASS IN REPEATING ROWS OF EIGHT
   • 1869
     • MENDELEEV, PRODUCED THE 1ST PERIODIC TABLE FOR HIS STUDENTS, HE ARRANGED THEM IN COLUMNS AND BASED ON SIMILAR PROPERTIES
     • HENEY MOSELEY, ARRANGED THE ELEMENTS IN ASCENDING ORDER OF THEIR ATOMIC NUMBERS
   • EARLY 1960
     • 60 ELEMENTS WERE KNOWN

4. PROPERTIES

   • ELECTRONEGATIVITY
     • THE ABILITY OF AN ATOM TO ATTRACT SHARED ELECTRONS IN A COVALENT BOND. THE ABILITY OF AN ATOM TO ATTRACT ELECTRONS TOWARD ITSELF.
   • ATOMIC SIZE
     • THE ATOMIC RADIUS OF AN ELEMENT IS A MEASURE OF THE SIZE OF ITS ATOMS, TYPICAL DISTANCE FROM THE CENTER OF THE NUCLEUS TO THE BOUNDARY OF THE SURROUNDING SHELLS OF ELECTRONS, ELECTRONS DO NOT HAVE DEFINITE ORBITS, OR SHARPLY DEFINED RANGES
   • IONIZATION ENERGY
     • THE ENERGY NEEDED TO REMOVE AN ELECTRON FROM AN ELEMENT IN THE GAS PHASE
   • ATOMIC RADIUS
     • THE DISTANCE BETWEEN THE CENTER OR NUCLEI OF THE NEIGHBORING ATOM. A MORE ACCURATE WAY OF DETERMINING AND DEFINING AN ATOM'S SIZE
   • ELECTRON AFFINITY
     • THE CHANGE IN ENERGY OF A NEUTRAL ATOM WHEN AN ELECTRON IS ADDED TO THE ATOM TO FORM A NEGATIVE ION

5. SUBMITTED BY:

6. TRENDS

   • THE ATOMIC RADIUS INCREASES FROM TOP TO BOTTOM IN A GROUP, AND DECREASES FROM LEFT TO RIGHT ACROSS A PERIOD
   • ELECTRON AFFINITY INCREASES FROM LEFT TO RIGHT ACROSS A PERIOD AND DECREASES FROM TOP TO BOTTOM ACROSS A GROUP
   • THE IONIZATION ENERGY DECREASES FROM TOP TO BOTTOM IN GROUPS, AND INCREASES FROM LEFT TO RIGHT ACROSS A PERIOD
   • THE ELECTRONEGATIVITY DECREASES FROM TOP TO BOTTOM IN GROUP AND INCREASES FROM LEFT TO RIGHT ACROSS A PERIOD