electrons and chemical bonding spring 2014 day 2

You Will Need:1. Pencil, Text Book- Periodic Table,

Colored Pencils2. Pick up 2 manilla folders3. Turn in STAR Cards 31-60 into the

box on the front table.4. You will be assigned a computer

after your STAR test to continue working on your Electrons and Chemical Bonding Worksheet

You will have 15 minutes to complete your STAR Quiz #2

When done:1)Turn quiz into Turn-in Tray2)Return Manilla folders to front bookshelf3)Sign out a Computer w/Mrs. M.4)Continue to work on completing pages 1-4 of your Electrons and Chemical Bonding Worksheet

Please make sure:1)You used your own words for the notes (except for vocabulary words)2)Highlighted important information3)Review and Reflect on ALL pages.

Everything on this planet is made of atoms from elements. Even though the number of elements on the Periodic Table is limited, joining the elements in different ways allows you to make a huge number of combinations.

 Chemical Bonding is the joining of atoms to

form new substances. The properties of these new substances are different from the properties of the original elements. When chemical bonds form, electrons are shared, gained or lost.

Everything on this planet is made of atoms from elements. Even though the number of elements on the Periodic Table is limited, joining the elements in different ways allows you to make a huge number of combinations.

 Chemical Bonding is the joining of atoms to form

new substances. The properties of these new substances are different from the properties of the original elements. When chemical bonds form, electrons are shared, gained or lost.

 Understanding the electron configuration, (Electron Dot,)

for each atom will help you understand how different elements will bond or not bond with other elements. 

Need to Know!

Not all the electrons in an atom are used to make chemical bonds. It is the electrons on Outer-Most Level or VALENCE electrons, (Electron-Dot) that determine how an atom will react (bond). REMEMBER: You can use your periodic table to determine valence values for most elements.

 Atoms want to be “happy” or stable….if they

have a full outer shell. Atoms that have fewer than eight valence electrons usually form bonds. The only time a full shell is equal to 2 if for the element Helium.

Element Bohr Model Lewis Dot (Symbol + Valence)

Lithium

Atomic #

Atomic Mass – Atomic #

Neon

Atomic #

Atomic Mass – Atomic #

Row =

Electrons= Protons =

Neutrons =

2

3-3+

7-3=

4

P = 3N = 4

21

Li

Row =

Electrons= Protons =

Neutrons =

P =10N =10 Ne

2

10-10+

20-10

10

28

valence

valence

Element Group Valence Bond or Not Bond

Hydrogen 1 1 Bond

Magnesium

Oxygen

Sulfur

Krypton

Lithium

Carbon

Compound Lewis Dot Bonding Config. Type of Bond and Why?

Sodium Fluoride (NaF)

Diatomic Fluoride (F2)

Hydrogen Fluoride (HF)

Watch the video clip on Covalent & Ionic Bonding (hyperlinked on Learning Point)

Question Answer

Ion • Charged atom• Caused by a transfer (lose or gain)

or shared electron

What are the characteristics of Ionic Bonds?

• Usually between Metals and Nonmetals

• Transfer of electrons – atoms become IONS

• Form Crystal Lattices• Brittle• High melting and boiling points• Dissolve easily in water• Form compounds• Specific shape

Bismut

h

Crystal Lattice

Question Answer

What are the characteristics of Ionic Bonds?

• Usually between Metals and Nonmetals• Transfer of electrons – atoms become

IONS• Form Crystal Lattices• Brittle• High melting and boiling points• Dissolve easily in water• Form compounds• Specific shape

Illustrate a neutrally charged Bohr Model of an aluminum atom.

Before you move to the next slide….try to draw this on your own and then check to see how you did.

If you made a mistake….figure out what you did incorrectly.

Question Answer

What are the characteristics of Ionic Bonds?

• Usually between Metals and Nonmetals• Transfer of electrons – atoms become

IONS• Form Crystal Lattices• Brittle• High melting and boiling points• Dissolve easily in water• Form compounds• Specific shape

Illustrate a neutrally charged Bohr Model of an aluminum atom.

P=13N=14

2 83

Question Answer

Illustrate a positively charged Bohr Model of an aluminum atom. (3+)

Before you move onto the next slide….try to draw this on your own.

Question Answer

Illustrate a positively charged Bohr Model of an aluminum atom. (3+)

Why is Al3+

considered an ion?

(Look at all the subatomic particles before you answer this question.)

P=13N=14

28

Forming Sodium Chloridehttp://www.youtube.com/watch?v=2mzDwgyk6QM

Before (pg. 233) After

Questions:1)Why does Sodium become an Ion? 2)Is it Positive or Negative? Why?3)Why does Chlorine become an Ion? 4)Is it Positive or Negative? Why?

Questions:1)Why do Sodium and Chlorine bond?2)What is the overall charge of the compound?3)Does NaCl have the same characteristics as Na and Cl?4)What are some unique characteristics of NaCl?

Question Answer

Characteristics of Covalent bonds

• Valance electrons are shared• More often between nonmetal• Low melting and boiling point• Free flowing but can be brittle• Form molecules• Usually do not have a specific

shape - flexible

View Video – Covalent Bonding – hyperlinked on Learning Point.http://www.youtube.com/watch?v=1wpDicW_MQQ

How many types of covalent bonds are shown in the video clip? ______

C6H10O5

C12H22O11

Molecule Illustration Explanation Electron Dot (Color Code each element)

1. What kind of bond does Hydrogen & Oxygen make?

2. How do you know?3. Why does one Oxygen

bond with two Hydrogen atoms?

http://www.youtube.com/watch?v=ulyopnxjAZ8&feature=relmfu Drawing Lewis Dot Diagram Bonds

P=8N=8

P=1N=0

P=1N=0

P=8N=8

P=1N=0

P=1N=0

How do we determine the type of bond in a compound?

• Identify class of elements• Same class usually covalent• Opposite class usually ionic

• Calculate the electronegativity factor

What is ELECTRONEGATIVITY? A measure of how much an element wants an electron

How do you know the electronegativity factor of an element?

Look it up (see next slide)

What are the determining values for each type of bond?

0-0.4 = Non-polar covalent

.41-2.0 = Polar covalent

>2.0 = Ionic

http://www.youtube.com/watch?v=7DjsD7Hcd9U

http://www.tutor-homework.com/Chemistry_Help/electronegativity_table/electronegativity.html

ELECTRONEGATIVITY VALUES

0-0.4 = Non-polar covalent.41-2.0 = Polar covalent>2.0 = Ionic

Let’s try a couple:

P=8N=8

P=1N=0

P=1N=0

H2OCalculate the electronegativity factor

H = 2.2O = 3.44

3.44 – 2.2 = 1.24

NaCl

0-0.4 = Non-polar covalent.41-2.0 = Polar covalent

>2.0 = Ionic

Polar Covalent

Ionic

Na = .93Cl = 3.16

3.16 - .93 = 2.23

Homework:

1)Ionic and Covalent Bonding – Due next Wed.

2)STAR Cards #31-30 – on 3x5 cards – Due Tomorrow at the beginning of class