1. ATOMS AND ELEMENTS UNIT 1: ST SCIENCE 10 ATOMIC MODELS
PERIODIC TABLE OF ELEMENTS
REPRESENTING MODELS

2. WHAT IS AN ATOM AN ATOM IS THE SMALLEST PARTICLE OF MATTER.
IT CANNOT BE DIVIDED CHEMICALLY
HOW SMALL IS AN ATOM?
- A SHEET OF PAPER IS ABOUT A MILLION ATOMS THICK
- A DROP OF WATER CAN CONTAIN MANY AS 10 SEXTILLION ATOMS ( )
-THE DIAMETER OF THE PERIOD AT THE END OF THIS SENTENCE HAS 50 TRILLION ATOMS LINED UP IN A ROW IN IT
WHAT IS AN ATOM

3. ATOMIC MODELS DALTON’S MODEL 1808
SOLID BALLS. DIFFERENT COLORS. DIFFERENT MASSES
CARBON OXYGEN
ALL ATOMS OF THE SAME ELEMENT ARE THE SAME
ALL ATOMS OF ONE ELEMENT ARE DIFFERENT FROM THOSE OF OTHER ELEMENTS
ELEMENTS CAN COMBINE
ATOMIC MODELS

4. ATOMIC MODELS THOMSON’S MODEL 1897
INCLUDED POSITIVE (PROTONS) AND NEGATIVE (ELECTRONS) CHARGES.
ZINC COPPER
- ADDED TO DALTON’S THEORY THAT ELEMENTS HAD BOTH POSITIVELY CHARGED AND NEGATIVELY CHARGED PARTS TO THEIR CORE
ATOMIC MODELS

5. ATOMIC MODEL RUTHERFORD’S MODEL 1911
FIRST TO INTRODUCE THE NUCLEUS, LIGHTWEIGHT WITH NEGATIVE CHARGED ELECTRONS SCATTERED RANDOMLY IN A LARGE SPACE OUTSIDE THE NUCLEUS.
BERYLIUM BERYLIUM
ATOMIC MODEL

6. ATOMIC MODELS RUTHERFORD-BOHR MODEL 1913
SMALL NUCLEUS(PROTONS AND NEUTRONS), MORE CONSISTENT ELECTRONS IN A SERIES OF ORBITS.
LITHIUM NICKEL
ATOMIC MODELS

7. PERIODIC TABLE OF ELEMENTS
METALS, NONMETALS, AND METTALOIDS
METALS
IDENTIFIED BY THE STAIRCASE SHAPED LINE THAT CROSSES THE RIGHT HAND SIDE OF THE TABLE.
METALS: GOOD CONDUCTORS OF ELECTRICITY AND HEAT. MALLEABLE AND DUCTILE SO THEY CAN BE EASILY SHAPED.
SHINY
ROOM TEMPERATURE THEY ARE SOLIDS (EXCEPT MERCURY)
THEY REACT WITH ACIDS
PERIODIC TABLE OF ELEMENTS

8. PERIODIC TABLE OF ELEMENTS
METALS, NONMETALS, METALLOIDS
NONMETALS
POOR CONDUCTORS OF ELECTRICITY AND HEAT
MOST ARE GASES AT ROOM TEMPERATURE
SOLID NONMETALS CAN BE REDUCED TO POWDER
PERIODIC TABLE OF ELEMENTS

9. PERIODIC TABLE OF ELEMENTS
METALS, NONMETALS, METTALOIDS
METTALOIDS
(ALSO CALLED SEMI-METALS)
SEVEN ELEMENTS WITH PROPERTIES OF BOTH METALS AND NONMETALS.
SOME CONDUCT WELL, SOME DON’T. FOR THIS REASON THEY ARE SEMI-CONDUCTORS USED IN TRANSITORS, INTEGRATED CIRCUITS, AND LASERS
PERIODIC TABLE OF ELEMENTS

10. PERIODIC TABLE OF ELEMENTS
GROUPS
THEY CORRESPOND TO THE COLUMN IN THE PERIODIC TABLE.
EACH GROUP SHARE A SET OF SIMILAR CHEMICAL PROPERTIES BECAUSE THEY ALL HAVE THE SAME NUMBER OF VALANCE ELECTRONS.
VALANCE ELECTRONS (THE NUMBER OF ELECTRONS IN THE OUTERMOST SHELL)
2 – 8 – 8 – 18 ETC
PERIODIC TABLE OF ELEMENTS

11. PERIODIC TABLE OF ELEMENTS
GROUPS
ALAKALI METALS
ALL THE METALS OF THE 1ST GROUP. SOFT AND HIGHLY REACTIVE. IN PURE STATE, THEY MOST BE STORED IN OIL
ALKALINE EARTH METALS
ALL THE METALS IN THE 2ND GROUP. HIGHLY MALLEABLE AND BURN EASILY IN THE PRESENCE OF HEAT.
HALOGENS
NONMETALS IN GROUP 17. THEY REACT EASILY TO FORM COMPOUNDS (SALTS AND DISINFECTANTS)
NOBLE GASES
RARE GASES OR INERT GASES. LAST COLUMN. VERY STABLE. THEY REACT MINIMALLY
PERIODIC TABLE OF ELEMENTS

12. PERIODIC TABLE OF ELEMENTS
PERIODS
CORRESPONDS TO THE ROW OF THE PERIDIC TABLE. ALL THE ELEMENTS HAVE THE SAME AMOUNT OF ELECTRON SHELLS
HAVE CORRESPONDING REPETITION IN THE PATTERNS OF THEIR PROPERTIES (P. 23)
MELTING POINT – TEMPERATURE OF SOLID TO LIQUID
BOILING POINT – TEMPERATURE OF LIQUID TO GAS
DENSITY – MASS PER UNIT OF VOLUME
ATOMIC RADIUS – DISTANCE FROM CENTER OF THE ATOM
FIRST IONIZATION ENERGY – ENERGY REQUIRED TO REMOVE OUTERMOST ELECTRON
ELECTRONEGATIVITY – ATTRACTING TO FORM BOND
PERIODIC TABLE OF ELEMENTS

13. PERIODIC TABLE OF ELEMENTS
ATOMIC NUMBER
REPRESENTS THE NUMBER OF PROTONS IN THE NUCLEUS OF AN ATOM
ATOMIC MASS
REPRESENTS THE RELATIVE MASS OF THE ATOM AN ELEMENT BASED ON CARBON’S 6 PROTONS AND 6 NEUTRONS MEASURING 12u
ISOTOPES
ADDED OR SUBTRACTED NEUTRONS DEPENDING ON THE ELEMENT
PERIODIC TABLE OF ELEMENTS

14. REPRESENTING ATOMS LEWIS NOTATION (P. 27)
A SIMPLER REPRESENTATION OF THE ATOM, IN WHICH ONLY THE VALENCE ELECTRONS ARE ILLUSTRATED.
REPRESENTING ATOMS

15. REPRESENTING ATOMS RUTHERFORD-BOHR MODEL (P. 28)
ALL THREE FACTS MUST BE REPRESENTED:
1- THE PERIOD (REPRESENTING THE NUMBER OF ELECTRON SHELLS IN THE ATOM)
2- THE GROUP (REPRESENTING THE NUMBER OF VALENCE ELECTRONS)
3- ATOMIC NUMBER(REPRESENTING THE NUMBER OF PROTONS AND ELECTRONS)
REPRESENTING ATOMS

16. REPRESENTING ATOMS SIMPLIFIED ATOMIC MODEL (P. 28)
WE ROUND THE MASS TO THE NEAREST WHOLE NUMBER.
WE SUBTRACT MASS – ATOMIC NUMBER TO FIND HOW MANY NEUTRONS THERE ARE
EXAMPLE: CHLORINE 35.45u = 35
35 – 17 = 18 THEREFORE 17 PROTONS 17 ELECTRONS 18 NEUTRONS
REPRESENTING ATOMS

17. REPRESENTING ATOMS BALL AND STICK MODEL
BALLS WILL MAKE UP THE ELEMENTS
STICKS WILL MAKE UP THE BONDS
REPRESENTING ATOMS