Zumdahl’s Chapter 8 Chemical Bonding: Stealing and Sharing of electrons.
Electrons and Chemical Bonding Day 1
Transcript of Electrons and Chemical Bonding Day 1
You Will Need:1. Pencil, Text Book- Periodic
Table, Colored Pencils2. Ionic & Covalent Bonding 2
pages-3 sides (Pick-up from bookshelf- Please Staple)
4. Log #3 Update5. Building Blocks of Matter –
Counting Atoms– Due tomorrow
Please SCHEDULE:
1. To take Retake Test #2
• 129/185 or lower
2. Starts Thursday of this week
3. Parent Signature and Corrections – due Wed.
• Please Pick up your belongings
1. Move to the back of the room
2. Take your new seat when your name is called
• Decide on your new job
• Manager, Materials Manager, Timer Designer, Oral Presenter
1. The substances on the left side of a periodic table are most likely this class of elements….
2. Which subatomic particle determines the charge of the atom?
3. The scientist who believed the atomic structure resembled the solar system?
4. The lease reactive elements on the Periodic Table are the ______________.
5. The type of electrons that determine how an atom will bond to another atom are the ___________________.
6. The subatomic particle responsible for determining the atom you are looking at are the ____________.
7. Why are elements’ atoms on the periodic table neutral?
8. When an element’s atomic structure has more or less neutrons we call this an ______.
9. What is the valence of Nitrogen? How do you know?
10. How many more electron bonds would Nitrogen need to have a full outer shell?
Timer Designers: In charge of today’s lesson on the computer (R & R Required)
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
10
10-10+
20-1010
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
Bismuth
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• 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? ______
C6H10O5C12H22O11
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
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
10
10-10+
20-1010
28
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)Building Blocks of Matter –
Counting Atoms – Due Tomorrow2)Test #2 Corrections and Signature
– Due Wednesday3) Ionic and Covalent Bonding – Due
Thursday4)STAR Cards #1-30 – on 3x5 cards
– Due Friday at the beginning of class