THE ATOM- Ms melisa mcalmont Physical science MATTER THE ATOM- Ms melisa mcalmont Physical science

WHAT IS AN ATOM? -IT IS THE SMALLEST OBJECT THAT RETAINS THE PROPERTIES OF AN ELEMENT -THE SMALLEST PARTICLE OF AN ELEMENT THAT CAN EXIST ALONE OR IN COMBINATION

THE TERM “ATOM” COMES FROM THE GREEK WORD WHICH MEANS INVISIBLE AND COULD NOT BE DIVIDED

COMPOSITION OF AN ATOM 1)PROTONS 2) NEUTRONS 3) ELECTRONS

THE BIG BANG THEORY IN 1929 THE AMERICAN ASTRONOMER EDWIN HUBBLE DISCOVERED THAT THE DISTANCES TO FAR AWAY GALAXIES WERE PROPORTIONAL TO THEIR RED SHIFTS IN 1927 GEORGE LEMAITRE’S PROPOSED THE BIG BANG THEORY THAT HUBBLE BASED HIS OBSERVATION ON. LEMAITRE PROPOSED THAT THE UNIVERSE EXPANDED EXPLOSIVELY FROM AN EXTREMELY DENSE AND HOT STATE, AND CONTINUES TO EXPAND TODAY.

DEFINITION OF KEY TERMS 1)ATOMIC NUMBER- THE NUMBER OF PROTONS IN THE NUCLEUS OF AN ATOM, WHICH DETERMINES THE CHEMICAL PROPERTIES OF AN ELEMENT AND ITS PLACE IN THE PERIODIC TABLE

2)THE MASS OF AN ATOM OF A CHEMICAL ELEMENT EXPRESSED IN ATOMIC MASS UNITS. IT IS ALSO THE EQUIVALENT TO THE NUMBER OF PROTONS, NEUTRONS IN THE ATOM(THE MASS NUMBER) OR THE AVERAGE NUMBER ALLOWING ABUNDANT ISOTOPES.

3)ELECTRON –A STABLE SUBATOMIC PARTICLE WITH A CHARGE OF NEGATIVE ELECTRICITY, FOUND IN ALL ATOMS AND ACTING AS THE PRIMARY CARRIER OF ELECTRICITY IN SOLIDS

2)PROTON- A STABLE SUBATOMIC PARTICLE OCCURRING IN ALL ATOMIC NUCLEI,WITH A POSITIVE ELECTRIC CHARGE EQUAL IN MAGNITUDE TO AN ELECTRON

3) NEUTRON- A SUBATOMIC PARTICLE OF ABOUT THE SAME MASS AS A PROTON BUT WITHOUT AN ELECTRIC CHARGE, PRESENT IN ALL ATOMIC NUCLEI EXCEPT THOSE OF ORDINARY HYDROGEN.

4) SUBATOMIC PARTICLES- A PARTICLE SMALLER THAN AN ATOM(E. G 4) SUBATOMIC PARTICLES- A PARTICLE SMALLER THAN AN ATOM(E.G. A NUETRON) OR A CLUSTER OF SUCH PARTICLES (E.G. AN ALPHA PARTICLE)

EXAMPLES OF AN ATOM

CAN U IDENTIFY THE SUB ATOMIC PARTICLES?

PERIODIC TABLE

WHAT IS THE PERIODIC TABLE? THIS IS A TABLE OF CHEMICAL ELEMENTS ARRANGED IN THE ORDER OF ATOMIC NUMBER,USUALLY IN ROWS,SO THAT ELEMENTS WITH SIMILAR ATOMIC STRUCTURE (AND SIMILAR CHEMICAL PROPERTIES)APPEAR IN VERTICAL COLUMNS

EXAMPLE OF A PERIODIC TABLE

1)TRY TO LIST THE 20 ELEMENTS OF THE PERIODIC TABLE IN WORDS/SONG ACTIVITY 1)TRY TO LIST THE 20 ELEMENTS OF THE PERIODIC TABLE IN WORDS/SONG

KEY TERMS GROUP-IS A COLUMN OF ELEMENTS IN THE PERIODIC TABLE OF CHEMICAL ELEMENTS. THERE ARE 18 NUMBERED GROUPS WHILE THE GROUPS BETWEEN 3 AND 4 ARE NOT NUMBERED PERIOD-IS A HORIZONTAL ROW IN THE PERIODIC TABLE. ALL ELEMENTS IN THE ROW HAVE THE SAME NUMBER OF ELECTRON SHELLS.

TRENDS IN THE PERIODIC TABLE TRENDS INCLUDE: -ELECTRONEGATIVITY -IONIZATION ENERGY -ELECTRON AFFINITY -ATOMIC RADIUS -MELTING POINT METALLIC CHARACTER

ELECTRONEGATIVITY TRENDS A CHEMICAL PROPERTY DESCRIBING AN ATOM’S ABILITY TO ATTRACT AND BIND WITH ELECTRONS

GRAPH SHOWING THE ELECTRONEGATIVE VALUES

NOTE -THE ELEMENTS ON THE LEFT SIDE OF THE PERIODIC TABLE LOSE ELECTRONS WHEN FORMING BONDS -THE ELEMENTS ON THE RIGHT SIDE OF THE PERIODIC TABLE GAIN ELECTRONS TO COMPLETE A VALANCE SHELL OF 8 ELECTRONS

NOTES FROM THE TOP TO BOTTOM DOWN A GROUP, ELECTRONEGATIVITY DECREASES -FROM LEFT TO RIGHT ACROSS A PERIOD OF ELEMENTS, ELECTRONEGATIVITY INCREASES FROM THE TOP TO BOTTOM DOWN A GROUP, ELECTRONEGATIVITY DECREASES

NOTES IONIZATION ENERGY- IS THE ENERGY REQUIRED TO REMOVE AN ELECTRON FROM A NEUTRAL ATOM IN ITS GASEOUS PHASE

TRENDS CONTINUED ELECTRON AFFINITY TRENDS-IS THE ABILITY OF AN ATOM TO ACCEPT AN ELECTRON. IT IS A MEASUREMENT OF THE ENERGY CHANGE THAT OCCURS WHEN AN ELECTRON IS ADDED TO A NUETRAL GAS ATOM

TRENDS ATOMIC RADIUS TRENDS- IS THE HALF DISTANCE BETWEEN THE NUCLEI OF TWO ATOMS. -ATOMIC RADIUS DECREASES FROM LEFT TO RIGHT WITHIN A PERIOD -ATOMIC RADIUS INCREASES FROM TOP TO BOTTOM WITHIN A GROUP. (ELECTRON SHIELDING)

TRENDS THE MELTING POINT IS THE AMOUNT OF ENERGY REQUIRED TO BREAK A BOND(S) TO CHANGE THE SOLID PHASE OF A SUBSTANCE TO A LIQUID

NOTES METALLIC CHARACTER OF AN ELEMENT IS HOW READILY N ATOM CAN LOSE AN ELECTRON. -METALLIC CHARACTER INCREASE LEFT ACROSS THE PERIOD AND DOWN THE GROUP -IT DECREASES RIGHT ACROSS THE PERIOD AND UP THE GROUP

METALLIC CHARACTER ON THE PERIODIC TABLE

isotopes WHAT ARE ISOTOPES? -EACH OF TWO OR MORE FORMS OF THE SAME ELEMENT THAT CONTAIN EQUAL NUMBERS OF PROTONS BUT DIFFERENT NUMBERS OF NUETRONS IN THEIR NUCLEI.THEY HAVE A DIFFERENT RELATIVE ATOMIC MASS BUT NOT IN CHEMICAL PROPERTIES. THEY ARE THE RADIOACTIVE FORM OF AN ELEMENT.

IMAGE OF AN ISOTOPE

DEFINITIONS CONTINUED 1)IONS- AN ATOM OR MOLECULE WITH A NET ELECTRIC CHARGE DUE TO THE LOSS OR GAIN OF ONE OR MORE ELECTRONS

EXAMPLE OF AN ION CREATION

DIFFERENCE BETWEEN AN ISOTOPE AND ION AN ION IS AN ATOM WITH A NET ELECTRIC CHARGE DUE TO THE LOSS OR GAIN OF ONE OR MORE ELECTRONS. AN ISOTOPE IS EACH OF TWO OR MORE FORMS OF THE SAME ELEMENT THAT CONTAIN EQUAL NEMBERS OF PROTONS BUT DIFFERENT NUMBERS OF NEUTRONS IN THEIR NUCLEI; DIFFERENT ATOMIC MASS

WHAT ARE HALOGENS? REACTIVE NON METALLIC ELEMENTS THAT FORM STRONGLY ACIDIC COMPOUNDS WITH HYDROGEN,WHICH SIMPLE SALTS CAN BE MADE. RELATED ELEMENTS INCLUDE: FLUORINE,CHLORINE, BROMINE, IODINE AND ASTATINE

WHAT ARE NOBLE GASES? NOBLE GASES HAVE COMPLETELY FILLED OUTER ELECTRON SHELLS .THEY RARELY REACT WITH OTHER ELEMENTS THEY BELONG TO GROUP 18. EXAMPLES INCLUDE: HELIUM,NEON,ARGON,KRYPTON,XENON AND RADON

ACTIVITY VIDEO ROLE PLAY EXERCISES

THE PERIODIC TABLE CALCULATIONS

ATOMS SIMPLIFIED

PERIODIC TABLE SIMPLIFIED

ELECTRONS, PROTONS, NEUTRONS SIMPLIFIED

HALOGENS AND NOBLE GASES SIMPLIFIED

Introduction to biochemistry WATER

ISOTOPES AND IONS SIMPLIFIED

HOW TO CALCULATE MASS NUMBER, NUMBER OF PROTONS, NUMBER OF ELECTRONS AND NEUTRONS SIMPLIFIED

EXAMPLE