Catalyst: Draw the atomic model and Lewis Dot Structure for F -

Catalyst: Draw the atomic model and

Lewis Dot Structure for F-

Thurs, Nov. 6th, 2008

Today’s Objective: SWBAT

Describe what bonds are.

Identify and draw atomic models of ionic compounds.

Ionic Bonds – Thurs, 11.06.2008

Matter Classification Review

How would you describe the following two images using the following terms: atom, molecule, element, and compound.

Matter Classification Review

Both of these are molecules and compounds.

Molecule b/c 2+ atoms

Compounds b/c 2 types of elements.


Matter Review

- Molecule = 2+ atoms- Compound = 2+ types of elements

Compounds

How are compounds held together? (Brainstorm in pairs)

They are held together by forces called chemical bonds.

These bonds form as a result of valence electrons interacting b/t elements.


Matter Review

Bonds

-Molecule = 2+ atoms- Compound = 2+ types of elements

- Forces that hold cmpds. together- Form b/c of valence e- interacting b/t elements

Valence ReviewAs the group number on the periodic table increases (as you move to the right), what happens to the number of valence electrons? (Think first!)

Valence ReviewAs group # increases, the # val. e- increases.

Why is this important?


Matter Review

Bonds

Val. e-



- As group # , val. e-

Valence ReviewAtoms WANT to have 8 electrons in their valence shell.

Which side of the periodic table would be more likely to receive electrons to make this happen?

Valence ReviewThe right side of the periodic table is more likely to receive electrons to make a full shell.

As group # increases, the ability to gain electrons, increases.


Matter Review

Bonds

Val. e-



- As group # , val. e- - As group # , ability to gain e-

Valence ReviewThe left side (metals) want to give away electrons & the right side (non-metals) want to accept electrons.

Valence ReviewIf an atom has few valence electrons, it wants to give them away (it is generous).

If an atom has many valence electrons, it wants to take more (it is greedy).


Matter Review

Bonds

Val. e-

Gaining/ Losing e-




-If fewer val. e-, wants to give e- away-If many val. e-, wants to take more e-

Lewis Dot Review (Left page)

What are the Lewis Dot Structures for Sodium & Chlorine?

Sodium – 1 val. e-

Chlorine – 7 val. e-

Lewis Dot Review (Left page)

Which one is more likely to give away electrons?

Sodium (has fewer val. e-)

Which one is more likely to accept electrons?

Chlorine (has more val. e-)

Ionic Bonds

What the heck does this have to do with bonds??

Ionic BondsIonic bonds occur when electrons in a compound are transferred from one atom to another.

Why?

Atoms that are more likely to give away electrons will transfer electrons to the atom that is more likely to accept electrons.


Val. e-

Gaining/ Losing e-

Ionic Bonds



- bond formed when e- transferred from one atom to another

Ionic BondsWhen an ionic bond is formed, atoms gain or lose electrons.

What are atoms that do not have the same number of protons & electrons called?

IONS

Steps for Creating Ionic Bonds

1. Draw the Lewis Dot structure for each atom.

2. Figure out which atom is more likely to give away electrons.

3. Figure out which atom is more likely to receive electrons.


Gaining/ Losing e-

Ionic Bonds

Ionic Bond Steps


- bond formed when e- transferred from one atom to another

1. Draw Lewis Dot structures.2. Figure which atom is more likely to give away electrons.3. “…” receive electrons.

Steps for Creating Ionic Bonds (Example – Left page)

1. Draw the Lewis Dot Structures for Sodium & Chlorine.

Sodium (Na): 1 val. e- Chlorine (Cl): 7 val. e-

Na Cl


2. Figure out which atom is more likely to give away electrons.

3. Figure out which atom is more likely to receive electrons.

Na Cl

Steps for Creating Ionic Bonds

4. Figure out how many electrons need to be transferred.

5. Draw an arrow showing transfer of electrons.

6. Determine and write charges of ions created.


Ionic Bond Steps

1. Draw Lewis Dot structures.2. Figure which atom is more likely to give away electrons.3. “…” receive electrons.4. Figure # e- to be transferred.5. Draw arrow showing e- moving.6. Write charges of new ions.


4. Figure out how many electrons need to be transferred.

1e- to be transferred

Na Cl


5. Draw an arrow showing transfer of electrons.

Na Cl


6. Determine and write charges of ions formed.

Na Cl

+ -

Steps for Creating Ionic Bonds (Example 2 – Left page)• Create an ionic bond between

Sodium (Na) and Flourine (F). (Take 3 minutes)

Steps for Creating Ionic Bonds (Example 2 – Left page)1. Draw Lewis Dot structures.

2. Figure which atom is more likely to give away electrons.

3. “…” receive electrons.

4. Figure # e- to be transferred.

5. Draw arrow showing e- moving.

6. Write charges of new ions.

Na F







Na F







Na F




4. Figure # e- to be transferred. (1)



Na F







Na F







Na F

+ -

Sample Problems (on white boards)

Draw the ionic bonds between the following elements:

1. Potassium & Flourine

2. Potassium & Chlorine

3. Hydrogen & Flourine

4. Chlorine & Hydrogen

5. Atom “X” with 6 valence electrons & Atom “Y” with 2 valence electrons.

6. Atom “Aa” with 5 total electrons & Atom “Bb” with 7 total electrons.

Documents

Catalyst: Draw the atomic model and Lewis Dot Structure for F -