Agenda:

Warm-up: Properties of Groups

Trends in properties How do we use the Periodic Table to predict properties of elements?

Reactivity: Atomic size Ionization EnergyElectronegativity

Return Test

Homework:

Objective: To understand the physical and chemical properties of atoms based on their position on the Periodic Table

Next Unit is forming bonds and compounds based on reactivity

Warm-up: Properties of Groups • Alkali Metals, Halogens, Noble Gases

• Which group is the least reactive? • In Group 1, which elements are most reactive? Why?• In Group 17, which elements are most reactive? Why? • Which Group contains all gases? • Which group always forms ionic compounds? • What other properties change in a Group when going

down the PT?

Predicting how easily an element reacts

What characteristics of an element impact how easily it reacts with other elements to form a chemical compound?

The electron arrangement of each atom determines its chemical behavior (how it reacts and bonds).

1. Forming ions based on number of valence electrons2. Atomic size3. Ionization energy4. Electronegativity

Atoms lose, gain or share valence electrons in order to be stable like the Noble Gases.Metals will: Non-metals will:

Forming Compounds

• Ions come together to form a ______________ ______________ .

• Many formula units are held together to make an _______ compound.

PERIODIC TRENDSUSING THE PERIODIC TABLE TO PREDICT PROPERTIES OF ELEMENTS AND GROUPS

Focus on Reactivity Atomic size Ionization EnergyElectronegativity

Atomic Radii

• Atomic Radius – measurement of the size (volume) of the atom

• Defined by the edge of its orbital but since the edges are fuzzy, difficult to determine

• Atomic Radii – half the distance between the nuclei of identical atoms that are bonded together

Ionization Energy• Ionization energy – the energy required to remove one electron

X + energy X+ + e-

• An electron can be removed from an atom if enough energy is absorbed (+) by the atom

• Note: measurements of this are made on individual atoms in gas phase to avoid interactions with nearby atoms

Adding energy = Endothermic

How do metal atoms lose electrons? Ionization energy• Ground State, Excited State, Ionization energy

Lithium

Electronegativty

•Electonegativity: An atoms’ ability to attract electrons from another atom

•Electron Affinity: The energy released when an electron is added to an atom

X + e- X- + energyReleasing energy = Exothermic

How do non-metal atoms gain electrons? Electronegativity• Large non-metal Small non-metal atom

atom

Examining properties & trends• Use Interactive Periodic Table –http://www.ptable.com/• Click on Properties

• Work in pairs• Each person completes the table

• When completed, investigate the properties of the transition metals

• Homework: Summary on a separate paper• Define the property• Summarize its trends: across periods and down groups• Summarize the characteristics of the property in each of the 3

groups studies

Linking Electron Arrangement to the PT

• Use Interactive Periodic Table –http://www.ptable.com/• Click on Orbitals

S P D F blocks Which are being filled?

Noble Gas Notation – using the PT

Rules for Group 1 & Group 2

Periods ?

Rules for Groups 13-18

Periods?

Rules for Transition Metals

Period ?

7. Reactivity

Group 18 (called the _______________) are ____________ (also called ________ or _____________), because:

Group 1 (called ____________) are the most reactive metals because:

Group 17 (called ___________) are themost reactive nonmetals because:

1 18

2 13 14 15 16 17

3 4 5 6 7 8 9 10 11 12

Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals

Reactivity: trends for metals and non-metals

Predicting Properties of Elements- based on the position on the Periodic

Table : Size; IE; EN

Property: which element has the largest value?Ca vs. Br C vs. Sn F vs. I Si vs. ClNa vs. P Li vs. KBe vs. O S vs. ArAl vs. S Ne vs. KrB vs. Al B vs. Ne

Periodic Trend Animation • http://faculty.ucc.edu/chemistry-pankuch/Amin.html• Atomic size

• Ionic size Interactive animations• Ionization • Electronegativity

• For later used: bond formation

Periodic Table• Objective: To understand the physical and chemical properties of atoms based on their position on the Periodic Table

• NC Essential Standards 1.3

• Physical properties:

• Chemical properties:

Periodic Tables • Groups • Http://www.ptable.com/Images/periodic%20table.png

• Interactive Periodic Table – useful for trends of properties• http://www.ptable.com/

PERIODIC TRENDSUSING THE PERIODIC TABLE TO PREDICT PROPERTIES OF ELEMENTS AND GROUPS

Focus on Reactivity Atomic sizeIonization EnergyElectronegativityElectron Affinity

Atomic Radii

• Atomic Radius – measurement of the size (volume) of the atom

• Defined by the edge of its orbital but since the edges are fuzzy, difficult to determine

• Atomic Radii – half the distance between the nuclei of identical atoms that are bonded together

Atomic Radii• Across Period:

• atoms get smaller• because of the increased number of protons attracting the electrons

• the electrons added in the same energy level do not shield electrons from nuclear charge

• Down Group:• atoms get larger• increases• because the energy levels being added to the atom

Atomic/Ionic Radii

Ionization Energy• Ionization energy – the energy required to remove one electron

X + energy X+ + e-

• An electron can be removed from an atom if enough energy is absorbed (+) by the atom

• Note: measurements of this are made on individual atoms in gas phase to avoid interactions with nearby atoms

Ionization Energy

Ionization Energy• Across Period:

• requires more energy to remove an electron so increases

• because electrons added in the same energy level do not shield electrons from nuclear charge

• Down Group:• requires less energy to remove electron so decreases

• because the valence electrons are farther away from protons attracting them

Ionization Energy

Ionization Energy

Electronegativty• Ability to attract electrons

• Non-metals (excluding Noble Gases)• High electronegativity

Electronegativity • Across Period:

• Increases

• Non-metals attract electrons

• Smaller atoms

• Down Group:• Decreases

• Protons in the nucleus are shielded by inner energy levels

• Harder to attract electrons

Electronegativity

Periodic Trend Animation • http://faculty.ucc.edu/chemistry-pankuch/Amin.html• Atomic size• Ionic size Interactive animations• Ionization • Electronegativity

• For later used: bond formation

1 18

2 13 14 15 16 17

3 4 5 6 7 8 9 10 11 12

Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals

Reactivity: trends for metals and non-metals

6. Octet Rule

Atoms tend to ______, ______, or _______electrons in order to have _____ valence

electrons._______ valence electrons gives stability.

Exception:

Duet rule: Hydrogen

7. Reactivity

Group 18 (called the _______________) are ____________ (also called ________ or _____________), because:

Group 1 (called ____________) are the most reactive metals because:

Group 17 (called ___________) are themost reactive nonmetals because:

1 18

2 13 14 15 16 17

3 4 5 6 7 8 9 10 11 12

Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals

Reactivity: trends for metals and non-metals

Predicting Properties of Elements- based on the position on the Periodic

Table : Size; IE; EN

Property: which element has the largest value?Ca vs. Br C vs. Sn F vs. I Si vs. ClNa vs. P Li vs. KBe vs. O S vs. ArAl vs. S Ne vs. KrB vs. Al B vs. Ne

Periodic Table videos• New Periodic Table Song• http://www.youtube.com/watch?v=IsBZx0tv6dQ• Prism website• http://www.gk12.ilstu.edu/chemistry/index.asp?page=perio

dicTable