post transition noble gasses halogens...transition metals lanthanides actinides post transition...
TRANSCRIPT
TRANSITION METALS
LANTHANIDES
ACTINIDES
POST TRANSITION METALS NON METALS
NOBLE GASSES
HALOGENS
SEMI METALS
Hydrogen is considered to be a group on its own
ALKALI METALS
ALKALINE EARTH METALS
TRENDS OF THE PERIODIC TABLE Chemistry 11Atomic Theory
WHICH ONE OF THE FOLLOWING ARE BIGGER?
1.Li or Na2.Cs or Rb3.F or Cl4.Pb or Si
WHICH ONE OF THE FOLLOWING IS BIGGER?
1. Na or Mg2. Na or Cl
TRENDS OF THE PERIODIC TABLE
3 factors are discussed when explaining above trends1. Nuclear Charge2. Shielding Electrons3. Number of Shells
We will be discussing the following trends1. Atomic Radius2. Ionization Energy3. Electronegativity
NUCLEAR CHARGE - LEFT TO RIGHT
vAtomic # increases = # of protons increase (more +ve charges)
Across The Periodic Table
OVERALL Pull on electrons due to nuclear charge INCREASES
-
++-
-+
-- -
-Electrons experience pull force from the positive protons in the nucleus.
NUCLEAR CHARGE – TOP TO BOTTOM
v Atomic # increases = # of protons increase (more +ve charge)
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OVERALL Pull on electrons due to nuclear charge INCREASES
SHIELDING ELECTRONS
----5P6N
Boron
-
SHIELDING ELECTRONS
----5P6N
Boron2 Shielding electrons
Outer Electrons being blocked by the inner electrons from nuclear charge
What are shielding electrons?
Electrons in the lower shells that block the pull of the protons.
Campfire Analogy – If someone is between you and the fire, you feel less heat.
-
SHIELDING ELECTRONS – LEFT TO RIGHT
-
--
-- -
-
9P10N
-
Beryllium 2 Shielding electrons
Fluorine2 Shielding electrons
--- 4P
5N-
OVERALL Number of Shielding electrons STAY THE SAME
Across The Periodic Table
SHIELDING ELECTRONS – TOP TO BOTTOM
10 Shielding electrons
18 Shielding electrons
OVERALL Number of Shielding electrons
INCREASES
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NUMBER OF SHELLS – LEFT TO RIGHT
Number of shells stay the SAME going across
Across The Periodic Table
NUMBER OF SHELLS – LEFT TO RIGHT
Number of shells INCREASE going down
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ATOMIC RADIUS
ATOMIC RADIUS – LEFT TO RIGHT
Nuclear Charge
• Increases • More protons pull electrons closer ∴ Atom is SMALLER
Number of Shells
• Stays the same in the same period
∴ NO CHANGE
OVERALL Atomic Radius DECREASES Going Across
Shielding Electrons
• Stay the same in the same period
∴ NO CHANGE
Across The Periodic Table
ATOMIC RADIUS – TOP TO BOTTOM
Nuclear Charge
• Increases• More protons pull electrons closer
∴ Atom is SMALLER
Number of Shells
• Increase going down
∴ Atom is LARGER
OVERALL Atomic Radius INCREASES Going Down
Shielding Electrons
• Increases• More electrons blocking the pull
of outer electrons.∴ Atom is LARGER
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Ato
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Rad
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Incr
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Atomic Radius Decreases
EXERCISE What is the largest atom in period 4?• Potassium
What is the largest and the smallest atom in group 2?• Largest – Radium • Smallest – Beryllium
Which is larger?• F or B?• Ba or Be?• Sr or P?
B
Ba
Sr
Open the refrigerator , put the giraffe in and close the door
Open the refrigerator , take out the giraffe put in the elephant and close the door
The Elephant
You swim across. All the crocodiles are attending the animal conference
JIGSAW ACTIVITY
Sitting in groups, you will be assigned one of three cards (Nuclear Charge, Shielding Electrons, and Number of
Shells.
Try to come up with answers to the questions individually and then discuss with group members.
JIGSAW ACTIVITY
Find two other classmates that have different cards than yours.
Take turns to explain your answers. Do the backside of Periodic Table Trends worksheet
JIGSAW ACTIVITYIn your groups come up with the following conclusions
OVERALL Atomic Radius INCREASES or DECREASES going across?
OVERALL Atomic Radius INCREASES or DECREASES going down?
ATOMIC RADIUS – IONS
CATIONS (+ve)
Lose electrons: Inter-electron repulsion (repulsion between electrons) decreases.
∴ Cation is SMALLER than its Atom
ANIONS (-ve)
Gain electrons: Inter-electron repulsion (repulsion between electrons) increases.
∴ Anion is LARGER than its Atom
IONIZATION ENERGYIt ALWAYS requires energy to remove an electron from an atom!!!
We ae breaking the electron’s attraction towards the nucleus.
DEFINITION
Ionization energy Energy required to remove an electron from the outer shell
IONIZATION ENERGY – LEFT TO RIGHT
Predict how nuclear charge, shielding electrons and number of shells would influence ionization energy going across the periodic table. Explain your answer.
Across The Periodic Table
IONIZATION ENERGY– LEFT TO RIGHT
Nuclear Charge
• Increases • More protons pull electrons closer• Harder to remove an electron∴ Ionization Energy INCREASES
Number of Shells
• Stays the same in the same period
∴ NO CHANGE
OVERALL Ionization Energy INCREASES
Shielding Electrons
• Stay the same in the same period
∴ NO CHANGE
Across The Periodic Table
IONIZATION ENERGY – LEFT TO RIGHT
Predict how nuclear charge, shielding electrons and number of shells would influence ionization energy going down the periodic table. Explain your answer.
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IONIZATION ENERGY– TOP TO BOTTOMNuclear Charge
• Increases • More protons pull electrons closer. • Harder to remove an electron.
∴ Ionization Energy INCREASES
Number of Shells
• Increases• Electrons move farther away from
the nucleus.• Easier to remove an electron.∴ Ionization energy DECREASES
OVERALL Ionization Energy DECREASES
Shielding Electrons
• Increases• More electrons block the pull of outer
electrons.• Easier to remove an electron.∴ Ionization Energy DECREASES
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Ioni
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Ionization Energy Increases
EXERCISE
What atom has the highest Ionization Energy?• He
Which has the lowest Ionization energy? Fe or B? Ba or Ba2+? Sr or P?
B
Ba
Sr
ELECTRONEGATIVITY DEFINITION
Ability of an atom to attract an electron from another atom.
If an atom has high electronegativity, it strongly attracts electrons from other atoms and might even remove the electron completely.
ELECTRONEGATIVITY – LEFT TO RIGHT
Predict how nuclear charge, shielding electrons and number of shells would influence electronegativity going across the periodic table. Explain your answer.
Across The Periodic Table
ELECTRONEGATIVITY– LEFT TO RIGHT
Nuclear Charge
• Increases • More protons, attract electrons more.• Atom is strong! • Easier to remove electron from another atom∴ Electronegativity INCREASES
Number of Shells
• Stays the same in the same period
∴ NO CHANGE
OVERALL Electronegativity INCREASES
Shielding Electrons
• Stay the same in the same period
∴ NO CHANGE
Across The Periodic Table
ELECTRONEGATIVITY – LEFT TO RIGHT
Predict how nuclear charge, shielding electrons and number of shells would influence electronegativity going down the periodic table. Explain your answer.
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ELECTRONEGATIVITY– TOP TO BOTTOMNuclear Charge
• Increases • More protons attract electrons more.• Atom is Strong!• Easier to pull an electron from another atom.
∴ Electronegativity INCREASES
Number of Shells
• Increases• Electrons are farther away from the proton.• Atom is weak!• Harder to pull electron from another atom.∴ Electronegativity DECREASES.
OVERALL Electronegativity DECREASES
Shielding Electrons
• Increase • Block the charge of protons.• Atom is weaker.• Harder to pull electron from another
atom.∴ Electronegativity DECREASES
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Elec
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Electronegativity Increases
MEASURING ELECTRONEGATIVITY
We use Pauling Scale to quantify electronegativity.
Highest electronegativity (value of 4) is assigned to Fluorine.
Values range down to Cs and Fr, which are the lease electronegative atoms (value of 0.7)
ELECTRONEGATIVITY AND IONIZATION ENERGY
If an atom has high electronegativity, it will also have a high ionization energy!
An atom that is strong, will not give away its electron easily!!!
HOMEWORK