Shows the trends in atomic size, ion size, electronegativity, ionization energy, electron affinity and metal vs. non metal properties.
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2. PERIODIC TRENDS OF THE
ELEMENTS
• CHEMICAL PROPERTIES
• PHYSICAL PROPERTIES
• ATOMIC RADII
• IONIC RADII
• IONIZATION ENERGY
• ELECTRON AFFINITY
• ELECTRONEGATIVITY
• METALLIC & NONMETALLIC CHARACTER
PERIODIC
TABLE ?
I INVENTED
IT !
MENDELEYEV
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3. DEFINITIONS OF PERIODIC PROPERTIES
• CHEMICAL PROPERTIES REFERS TO THE TENDENCY OF
ATOMS TO COMBINE WITH OTHER ELEMENTS AND/ OR
MOLECULES TO FORM COMPOUNDS.
• PHYSICAL PROPERTIES REFERS TO CHARACTERISTICS
SUCH AS DENSITY, PHYSICAL STATE (SOLID, LIQUID OR
GAS), ELECTRICAL AND THERMAL CONDUCTIVITY,
MALLEABILITY (CAN BE HAMMERED INTO SHAPE),
DUCTILITY (CAN BE STRETCHED), COLOR, LUSTER
(SHININESS), BRITTLENESS, ETC.
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4. DEFINITIONS OF PERIODIC PROPERTIES
(CONT’D)
• ATOMIC RADII IS MEASURED AS ONE HALF OF THE
DISTANCE BETWEEN THE NUCLEI OF TWO ADJACENT
SIMILAR ATOMS (IT MEASURES ATOMIC SIZE)
• IONIC RADII IS MEASURED AS ONE HALF OF THE
DISTANCE BETWEEN THE NUCLEI OF TWO ADJACENT
SIMILAR IONS (IT MEASURES ION SIZE)
• IONIZATION ENERGY MEASURES THE ENERGY NEEDED
TO REMOVE AN ELECTRON FROM A FREE ATOM IN THE
GAS STATE (IT MEASURES HOW TIGHTLY ELECTRONS
ARE BOUND TO AN ATOM)
• ELECTRON AFFINITY MEASURES THE ENERGY
RELEASED WHEN AN ELECTRON IS ADDED TO A FREE
ATOM IN THE GAS STATE ( IT MEASURES HOW WELL
ATOMS ATTRACT ELECTRONS)
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5. DEFINITIONS OF PERIODIC PROPERTIES
(CONT’D)
• ELECTRONEGATIVITY MEASURES THE
ELECTRON ATTRACTING ABILITY OF AN ATOM
WHEN IT IS BONDED TO ANOTHER ATOM
• METALLIC CHARACTER MEASURES THE
TENDENCY OF AN ELEMENT TO ACT AS A METAL
IN THINGS SUCH AS CONDUCTIVITY, TENDENCY
TO LOSE ELECTRONS, SHININESS, MAEBILITY
AND DUCTILITY
• NONMETALLIC CHARACTER MEASURES THE
TENDENCY OF AN ELEMENT TO ACT AS A
NONMETAL IN THINGS SUCH
NONCONDUCTIVITY, TENDENCY TO GAIN
ELECTRONS, LOW LUSTER AND BRITTLENESS.
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6. GENERAL ORGANIZATION OF THE
PERIODIC TABLE
• COLUMNS (FAMILIES) CONTAIN
ELEMENTS WITH SIMILAR VALENCE
ELECTRON CONFIGURATIONS (ns1, ns2, ns2
np3, ETC.) AND SIMILAR CHEMICAL
PROPERTIES
• ROWS (PERIODS) CONTAIN ELEMENTS
WITH VALENCE ELECTRONS AT THE SAME
ENERGY LEVEL (n=1, n=2, n=3, ETC.)
• BLOCKS OF ELEMENTS CONTAIN ATOMS
WITH THE SAME VALENCE ELECTRON
ORBITAL TYPE (s, p, d OR f)
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7. s
B
L
O
C
K d BLOCK p BLOCK
I
N
E
R
T
G
A
S
f BLOCK
metals non metals
METALLOIDS
Orbital Blocks on the Periodic Table
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8. COMMON CHEMICAL FAMILES & THEIR PROPERTIES
COLUMN I (ALKALI METALS) Li, Na, K, Rb, Cs AND Fr
• FORM +1 CATIONS
• ARE HIGHLY METALLIC
• REACTION READILY AND RAPIDLY WITH WATER TO FORM
HYDROXIDES AND HYDROGEN GAS
• REACT WITH THE HALOGENS (COLUMN VII) TO FORM SALTS WITH
FORMULA TYPE MX (FOR EXAMPLE NaCl OR KBr)
• VALENCE ELECTRONS ARE ns1
• COLUMN II (ALKALINE EARTH METALS) Be, Mg, Ca, Ba, Sr AND Ra
• FORM +2 CATIONS
• ARE HIGHLY METALLIC
• REACTION READILY AND RAPIDLY WITH WATER TO FORM
HYDROXIDES AND HYDROGEN GAS
• REACT WITH THE HALOGENS TO FORM SALTS WITH FORMULA
TYPE MX2 (FOR EXAMPLE MgBr2 OR BaCl2)
• VALENCE ELECTRONS ARE ns2
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9. COMMON CHEMICAL FAMILES & THEIR
PROPERTIES (CONT’D)
• COLUMN VII (COLUMN 17 ON SOME PERIODIC
TABLES) HALOGENS F2,Cl2, Br2, I2 AND At2
• ALL ARE DIATOMIC ELEMENTS (OCCUR AS A
MOLECULE CONSISTING OF TWO ATOMS
• ARE HIGHLY NONMETALLIC
• REACT READY AND RAPIDLY WITH METALS
TO FORM SALTS
• OCCUR IN ALL THREE PHASES AT ROOM
TEMPERATURE F2 AND Cl2 ARE GASES, Br2 IS A
LIQUID AND I2 IS A SOLID
• VALENCE ELECTRONS ARE ns2 np5
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10. COMMON CHEMICAL FAMILES & THEIR
PROPERTIES (CONT’D)
• COLUMN VIII (COLUMN 18 ON SOME PERIODIC
TABLES) INERT GASES, ALSO CALLED NOBLE GASES
OR RARE GASES
• ALL ARE UNREACTIVE UNDER ORDINARY CONDITIONS
• ALL HAVE COMPLETED OUTER ENERGY LEVELS
• ALL ARE GASES AT ROOM TEMPERATURE AND
PRESSURE
• THEIR ELECTRON CONFIGURATIONS ( ns2 np6 ) SET
THE STANDARD FOR CHEMICAL STABILITY WHICH
MOST OTHER ELEMENTS ATTEMPT TO ACHIEVE
THROUGH CHEMICAL REACTION.
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11. C C
O O
L L
M M
U U
N N
I II
Transitional
Metals
C
O
L
M
U
N
V
I
I
I
N
E
R
T
G
A
S
E
S
LANTHANIDE SERIES
ACTINIDE SERIES
Alkali metals
Alkaline Earth Metals Halogens
CHEMICAL FAMILIES
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13. WHAT FACTORS DETERMINE THE PERIODIC
TRENDS OF THE ELEMENTS ?
(1) THE NUMBER OF PROTONS AND ELECTRONS AN ATOM
CONTAINS (MORE PROTONS CREATE A GREATER
NUCLEAR CHARGE WHICH ATTRACTS ELECTRONS
MORE STRONGLY
(2) DISTANCE SEPARATING THE OUTER ELECTRONS
(VALENCE ELECTRONS) AND THE NUCLEUS (WHEN
ELECTRONS ARE CLOSER TO THE NUCLEUS THEY ARE
HELD MORE TIGHTLY)
(3) PAIRING OF ELECTRONS IN THE OUTER ENERGY LEVEL
ORBITALS (PAIRED ELECTRONS ARE MORE STABLE
THAN UNPAIRED ELECTRONS)
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14. FACTORS WHICH DETERMINE THE PERIODIC
TRENDS OF THE ELEMENTS (CONT’D)
•(4) THE SYMMETRY OF OUTER ENERGY LEVEL ORBITAL
POPULATIONS (GREATER SYMMETRY OF ELECTRON
POPULATIONS GIVES MORE STABILITY)
•(5) PROXIMITY OF OUTER ENERGY LEVEL ORBITALS TO
EACHOTHER (WHEN ORBITALS ARE CLOSE TO EACHOTHER
IN ENERGY THE ORDER OF ORBITAL FILLING MAY CHANGE.
THIS IS ESPECIALLY TRUE FOR THE TRANSITATIONAL
ELEMENTS)
•(6) THE EXTENT TO WHICH THE OUTER ENERGY LEVEL IS
FILLED (ATOMS ATTEMPT TO BECOME ISOELECTRONIC WITH
THE NEAREST INERT GAS BY GAINING OR LOSING
ELECTRONS, WHICH EVER IS EASIEST)
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15. FACTORS THAT DETERMINE THE PERIODIC
TRENDS – ATOMIC RADII
•AAS WE MOVE ACROSS A ROW (PERIOD) FROM LEFT TO
RIGHT ON THE PERIODIC TABLE, ATOMS BECOME
SMALLER AS THE ATOMIC NUMBER BECOMES LARGER.
THIS INCREASE IN NUCLEAR CHARGE ALLOWS THE
NUCLEUS TO PULL IN THE ELECTRONS MORE TIGHTLY
AND THEREBY REDUCE ATOMIC SIZE (RADIUS).
•AAS WE MOVE DOWN A COLUMN ON THE PERIODIC
TABLE, ELEMENTS CONTAIN MORE ELECTRONS AND
MORE ENERGY LEVELS BECOME POPULATED RESULTING
IN AN INCREASE IN ATOMIC SIZE (RADIUS). REMEMBER
THAT COMPLETING A PERIOD ON THE PERIODIC TABLE
RESULTS IN A COMPLETED ENERGY LEVEL WITHIN THE
ATOM !
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16. TRENDS OF THE ELEMENTS ONTHE
PERIODIC TABLE (ATOMIC RADII)
• SIZE OF ATOMS DECREASES
S
I
Z
E
I
N
C
R
E
A
S
E
S
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17. FACTORS THAT DETERMINE THE PERIODIC
TRENDS – IONIC RADII
•MMETAL ATOMS LOSE ELECTRONS TO BECOME ISOELECTRONIC WITH
THE INERT GASES. ALKALI METALS (COLUMN I) FOR EXAMPLE NEED
LOSE ONLY ONE ELECTRON TO BECOME ELECTRONICALLY LIKE THE
NEAREST NOBLE GAS.THIS IS MUCH EASIER THAN GAINING SEVEN OR
MORE ELECTRONS. ALKALINE EARTH METALS NEED TO LOSE ONLY
TWO ELECTRONS TO ACHIEVE THE ISOELECTRONIC STATE.THIS IS
MUCH EASIER THAN GAINING SIX OR MORE ELECTRONS
•BBY CONSTRAST, NONMETALS GAIN ELECTRONS TO BECOME
ISOELECTRONIC WITH THE INERT GASES. HALOGENS (COLUMN VII)
NEED TO GAIN ONLY ONE ELECTRON TO ACHIEVE THE ISOELECTRONIC
STATE. THIS IS MUCH EASIER THAN LOSING SEVEN OR MORE
ELECTRONS. THE OXYGEN GROUP(COLUMN VI) NEEDS ONLY TO GAIN
TWO ELECTRONS AGAIN EASIER THAN LOSING SIX OR MORE
ELECTRONS.
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