Unit 4 bonding lesson 4

Announcements/Reminders

Agenda:

​

• Monday 10/23- Lab on properties of ionic & covalent compounds

• wed 10/25- Bonding and lab quiz on ionic/covalent

• Thursday 11/2- Unit 4 Bonding test

• Bonding "pre-test"

• Le​wis structure of covalent compounds

• coordinate covalent bonds, polyatomic ions

Bellwork:

form on GC​​

​Monday 10/24: Unit 4: coordinate covalent bonds, polyatomic ions

​Determining Types of Bonds

If the difference in electronegativity is between:

1.8 to 4.0:  Ionic

0.4 to 1.7:  Polar Covalent

0.0 to 0.3:  Non-Polar Covalent

​A dipole moment is a measure of the polarity of a molecule.

​Drawing Lewis Dot structures of covalent compounds

1. Total all valence electrons

2. Determine the central atom (usually the element that there is only 1 of)

3. Draw single bonds to central atom

4. Assign remaining valence electrons as lone pairs to outer atom

5. Move electrons to create double bonds and triple bonds as needed to make all atoms "happy" (give all atoms an octet)

Let's try these!

​H₂O

​NH₃

​F₂ O₂ N₂

​HCN^-1

​CO₂

Total all valence electrons

Determine the central atom (usually the element that there is only 1 of)

Draw single bonds to central atom

Assign remaining valence electrons as lone pairs to outer atom

Move electrons to create double bonds and triple bonds as needed to give all atoms an octet​

Draw the Lewis dot diagram of each atom

Label each atom with the # of electrons it needs to be happy

Start with the atom that needs the least and draw a line to represent the covalent bond between the 2 atoms

Continue adding bonds between the atoms until all atoms are “happy”

Move electrons to create double bonds and triple bonds as needed

​Drawing Lewis Dot structures of covalent compounds

1. Draw the Lewis dot diagram of each atom

2. Label each atom with the # of electrons it needs to be happy

3. Start with the atom that needs the least and draw a line to represent the covalent bond between the 2 atoms

4. Continue adding bonds between the atoms until all atoms are “happy”

5. Move electrons to create double bonds and triple bonds as needed

Some text here about the topic of discussion

Monoatomic Ions vs Polyatomic Ions

• Monoatomic ions are made up of one type of atom

  • Li^+1, Mg⁺², Cl^-1​

• Polyatomic ions have either multiple atoms and/or different types of atoms

  • ​NO₃^-1 =Nitrate

  • Follow the same rules for forming compounds as monoatomic ions

Experience Chemistry | Lesson 3.1

​Video: coordinate covalent bonds

(watch first 6 minutes, last ​3 are optional)

Metallic Bonds

• Form between the cations of the metal(s).

• Orbitals overlap, electrons free to roam

• Sea of electrons

Metallic Bond

Alloys "solution of metals"

Multiple Choice

The chemical bond between a Ba and a Br will be a(n) _____ bond.

• metal

• ionic

• covalent

• polar

Multiple Choice

The chemical bond between N and another Br will be a ________ bond.

• metal

• ionic

• covalent

• polar

Multiple Choice

Elements on the LEFT side of the periodic table will most likely form:

• Positive ions
• Negative ions
• Neutral Ions
• None of these

Multiple Choice

Force that holds together atoms in a substance.

• compound
• ion
• chemical bond
• ionic bond

Multiple Choice

What type of bond will conduct electricity in a dissolved state?

• ionic

• covalent

Multiple Choice

In metallic bonds electrons:

• shared

• move around the nuclei randomly

• transferred

Multiple Choice

Alloys are important because

• their properties are often superior to the component elements

• their properties are a blend of the component elements

• they never corrode

• they are less expensive than their component elements.

Multiple Choice

Why are metals good conductors?

• they have mobile electrons

• they have mobile atoms

• they have crystal structures that can rearrange

• they have mobile protons

Multiple Choice

In metals, the valence electrons are

• attached to the most positive ions

• shared by all of the atoms

• are bonded to the least electronegative element

• shiny

Multiple Choice

Which type of bond creates a "sea" of electrons between atoms?

• Ionic Bonds

• Covalent Bonds

• Metallic Bonds

• Saving Bonds

Multiple Choice

Predict the bond that will form between Be and F.

• Ionic
• Covalent

Multiple Choice

Predict the bond that will form between Se and Cl.

• Ionic
• Covalent

Multiple Choice

Predict the bond that will form between Sr and S.

• Ionic
• Covalent

Multiple Choice

A chemical bond between oppositely charged ions.

• compound
• ion
• covalent bond
• ionic bond

Multiple Choice

Is this compound Ionic or Covalent: Ca₃(PO₄)₂

• ionic

• covalent