The Periodic Law (Periodic Table)

1
The Periodic Law (Periodic Table)

• CHAPTER FIVE

2
Brief History

• Original periodic table was constructed by Dmitri
  Mendeleev. This periodic table consisted of
  about 60 elements and was arranged in order of
  increasing atomic mass

3
Modern Periodic Table

• Our periodic table is based on the work of Henry
  Mosely, who arranged the elements in order of
  increasing atomic number

4
Periodic Law

• Moselys and Mendeleevs periodic table follows
  periodic law
• This means that if elements are arranged in
  increasing atomic , they will fall into groups
  that have similar properties.

5
Modern Periodic Table

• 18 vertical group/families
• 7 horizontal periods
• Divided into two main parts, metals and
  nonmentals.

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Left Side of the periodic table

• Metals
• Shiny
• Malleable
• Ductile
• Conducts electricity
• Conducts Heat
• Mostly solids

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Group 1 Elements

• Alkali Metals
• Most reactive of the metals
• Mostly Soft Solids

8
Group 2 Elements

• Alkaline Earth Metals
• Still very reactive
• More dense than the group 1 metals

9
Groups three through twelve

• Transitional Metals
• Elements transition from Metals to non-metals
  as you move across the table
• Most Transition metals have metallic properties

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The Others

• Groups 13-16
• Other Metals (Have metallic properties)
• Al, Ga, In, Sn, Bi, Pb, Tl
• Metalloids-Boron, Silicon, Germanium, Arsenic,
  Antimony, Tellurium
• Properties of both metals and non-mentals
• Semiconductors-used in electronics
• Other Non-Metals (Have non-metal properties)
• C, N, O, P, S, Se, H

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Right side of periodic table

• Non-Metals
• Do not conduct electricity or heat well
• Some brittle solids
• Some gasses

12
Group 17

• Halogens
• Non-metal
• most reactive of nonmetals.

13
Group 18

• Noble gases
• Nonmetals
• Least reactive of non-metals

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Check for understanding

• Which group/family is each element in?
• Al
• Ar
• K
• Pd
• Br
• Ca
• Zn
• Si

Based on the group/family each element below are
in, name 2 properties of 9. K 10. P 11. Cl 12.
Ga
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Periodic Trends

• The tendencies of certain elemental
  characteristics to increase or decrease as one
  progresses along a row or column of the periodic
  table of elements.

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Atomic Radii

• Atomic Radii-The distance from the center of the
  nucleus to the edge of the atoms electron cloud.

Atomic Radii
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Atomic Radii Trending Activity

• Grapher
• Straw Cutter
• Recorder
• We will use our current knowledge of the atom to
  try and predict the trend for atomic radii.
• We will then test our hypothesis by actually
  graphing real data and then making a 3-D model of
  the trend.

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Atomic Radii Continued

• Trend in each period
• Why do you think the radius decreases to the
  right if there are more protons to the right?
  Shouldnt that make the radius increase?
• As there are more protons they pull more strongly
  on the electrons that are surrounding them.
• Each period is within the same energy level.

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Atomic Radii Continued

• Trend in each group
• Why do you think the radius increases as you go
  down a group if more protons means they pull
  harder on the electrons?
• As you go down a group you are adding energy
  levels which makes the radius increase.

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Atomic Radii Continued

• Periodic Table Trend
• Increases to the left
• Increases going down

Increasing Size
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Atomic Radii Practice

• In each pair which of the following has the
  largest Atomic Radii?
• K or Ni
• Ne or Xe
• Rb or In
• Arrange the following in order of increasing
  atomic radii?
• 4. Al, K, Ne, H
• Answer H, Ne, Al, K,
• 5. Will a larger atomic radii make an atom more
  or less likely to give away an electron?

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Quiz

• Place the following in order using decreasing
  Atomic Radii Au, Ba, O, Cl Pb
• Cl or I
• Which of the above pair has the largest atomic
  radii?
• Why does the table trend that way?
• Who created the 1st periodic table?
• What was the 1st periodic table arranged by?
• The vertical columns are called what?
• Elements within the same column will have
  _________ properties.
• What is the name of each of the following groups?
• 18
• 2
• 1
• Which group name does Ge fall under?
• Name 4 popertiesA

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Ionization Energy (IE)

• 1st Ionization Energy-Energy required to remove
  one electron from an un-bonded atom. (individual
  atoms)
• Basically How hard is it to get an electron away
  from an atom?

No, Mine!
Mine!
e-
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Ions

• If enough energy is input into an atom, an
  electron will be removed. This forms an Ion.
• ION-an atom that has a positive or negative
  charge.

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Ionization Energy (IE)

• A lost electron will create a Positive Ion
• Positive Ion is a Cation

Pawsitive )
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Ionization Energy (IE)

• A gained electron will create a negative ion
• Negative ions are called Anions

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• Define Valence Electrons
• Define Lewis Dot Noation
• In the above configurations underline the highest
  energy level represented
• (not the orbitals, just the energy levels)
• Circle the electrons in each of those highest
  energy levels

Group 1 elements Electron Configuration Notation of Valence Electrons Lewis Dot Notation Borh Model
Li
K
Cs
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Valence Electrons and Ionization Energy
Make the same chart for each of the elements in
the following Groups as well

• Group 2
• Be
• Ca
• Ba
• Group 13
• B
• Al
• Ga

• Group 14
• C
• Si
• Group 15
• N
• P
• Group 16
• O
• S

• Group 17
• F
• Cl
• Group 18
• He
• Ne
• Ar

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Ionization Energy (IE) Continued

• Trend across a period?
• Decreases to the left
• Trend in a group/family?
• Decreases going down
• Which Group would have the lowest first
  Ionization energy? (who is it easiest to take an
  electron from?)
• Group 1
• Why?
• They want to get rid of that 1 valence electron
• Which group would have the highest first
  ionization energy?
• Group 18
• Why?
• They do not want to lose one of their 8 valence
  electrons ( they are happy the way they are)

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Ionization Energy

• Periodic Table Trend
• Decreases to the left
• Decreases going down

Decreasing
Decreasing
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Ionization energy practice

• Which element within the following pairs has the
  highest ionization energy?
• K or Be
• B or Ga
• O or Ca
• Ar or Sb
• Arrange the following in decreasing Ionization
  energy (meaning from Highest to lowest)
• Li, O, C, K, Ne, F

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Electron Affinity

• Electron Affinity-The energy change that occurs
  when an individual atom gains an electron.
• The more an atom loves getting another electron
  the more the energy it will release.

. .
_
. .

Electron
Atom
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Electron Affinity

• Which group is happiest to take on an electron?
• Group 17 Why?
• They are 1 electron away from a full outer shell
  (Valance Shell)

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Electron Affinity

• Which groups care nothing for additional
  electrons?
• Group 1 and Group 18? Why?
• Group 18 is totally happy with their 8 electrons
• Group 1 is closer to being happy by giving away
  its 1 valance electron.

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Electron Affinity

• Periodic Table Trend
• Decreases to the left
• Decreases going down

Decreasing
Decreasing
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Electron Affinity

• Which of the following has the greatest electron
  affinity?
• Al or Br
• O or C
• Xe or F
• Arrange by increasing Electron Affinity
• Cl, K, Fr, I
• AnswerFr, K, I, Cl

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Electronegativity

• Electronegativity-Measurement of how strongly one
  atom attracts the electrons of another atom in a
  compound.
• Developed by Linus Pauling
• Which element do you think would be the most
  electronegative?
• Fluorine-4.0. All other values are calculated in
  relation to Fluorines value.
• Scientest just picked the number 4. It wasnt
  really based on anything.

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Electronegativity (FON)

• Oxygen, Nitrogen and then the other halogens are
  the most Electronegative after fluorine.
• F, O, N Top 3 highest electronegativity

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Electronegativity

• Periodic Table Trend
• Decreases to the left
• Decreases going down

Decreasing
Decreasing
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Electronegativity Practice

• Which of each pair has the greatest EN?
• a. Ca or Ga
• b. Br or As
• c. Li or O
• d. Ba or Sr
• e. Cl or S
• f. O or S
• Rank the following elements by increasing EN
  sulfur, oxygen, neon, aluminum.
• Answer Ne,Al,S,O

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Trending Challenge
 Terms Definition in your own words Single atoms or bonded atoms? Element with smallest Element with largest
Atomic Radii
Ionization Energy
Electron Affinity
Electro-negativity

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Trending Challenge
 Terms Definition in your own words Single atoms or bonded atoms? Element with smallest Element with largest
Atomic Radii The Radius of the atom (center of nucleus to edge of electron cloud)   Single Helium-He Francium-Fr
Ionization Energy  The energy needed to take an electron from a neutral atom Single Francium-Fr Helium-He
Electron Affinity  Energy given off when an neutral atom gains an electron Single Francium-Fr Flourine-F (Helium doesnt want electrons)
Electro-negativity  How strongly one atom pulls on the electrons of another atom in a compound Bonded  Francium-Fr Flourine-F (Helium doesnt want electrons)
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Review

• 1. The elements characterized as nonmetals are
  located in the periodic table at the
• (A) left (B) bottom (C) center (D) top right
• 2. Which is the atomic number of an alkali metal?
  
• (A) 10 (B) 11 (C) 12 (D) 13.
• 3. Which element is a halogen?
• (A) iron (B) nitrogen (C) iodine (D) neon
• 4. Which Group 17 element has the least tendency
  to gain electrons?
• (A) fluorine (B) iodine (C) bromine (D)
  chlorine.
• 5. The alkaline earth element having the largest
  atomic radius is found in Period
• (A) 1 (B) 2 (C) 6 (D) 7.
• 6. Which of the following atoms will lose an
  electron the easiest?
• (A) potassium (B) calcium (C) rubidium (D)
  strontium