1. Before Bell Rings Have your Periodic Trends packet out for me to check.

2. ETD #
What is the trend in electronegativity as we move left to right on the PT? Top to Bottom?
Why don’t the noble gases have values for electronegativity?

3. ETD#
What is the general trend in electronegativity as we move left to right on the PT? Top to Bottom?
Increases L to R, Decreases T to B
Why don’t the noble gases have values for electronegativity?
Because they have a full outer shell, they don’t want to attract electrons. They are “happy”.
Electronegativity increases left to right because the atoms can get closer due to smaller atomic radius. This allow the nucleus to pull on the electrons of the atom more strongly. It decreases top to bottom for the same reason, only now the atom is getting lager due to more energy levels being added.
Full outer shell for noble gases means they don’t want to take in or give away electrons.

4. Learning Targets
I can determine what type of bond two elements will have.
I know the different groups and regions of the periodic table.

5. Test Review Questions
I just made a new page on my Swift Site with test review questions and answers.

6. Bonding 3 Types Ionic bonds Polar Covalent Non-Polar Covalent
Atoms take in or give away electrons, bond comes from the attraction between the oppositely charged ions.
Polar Covalent
Atoms share the electrons, but one has a bigger share than the other.
Non-Polar Covalent
Atoms share the electrons between themselves equally
3 types of bonds
Ionic bonds happen when electrons move from one atom to another in order to complete the outer shell of both. This makes one atom a positive ion and one a negative ion. The bond comes from these oppositely charged ions attraction to each other.
Covalent bonds happen when two atoms are sharing the electrons between themselves. The bond comes from this sharing of the electrons. If they are sharing equally, it will be a nonpolar covalent bond. It is nonpolar because the electrons are not more concentrated in one area. This means there won’t be a part of the bond that is more negative and one that is more positive. If the atoms are sharing the electrons but unequally the bond will be polar. This means one atom has a bigger share of the electrons and one has a smaller share. The atom with the larger share will be at the negative end of the bond and the atom with less of a share will be at the positive end.

7. Octet rule – elements are most stable when 8 valence e-
*all elements want to be like the noble gases
*atoms gain or lose e- to be satisfied
How many electrons will the following need to gain or lose to be satisfied. What is the resulting charge S
[Ne] _↓_ _↓_ ___ ___
needs to gain 2 electrons = S2- Mg
[Ne] _↓_ _↓_ _↓_ _↓_ _↓_
needs to lose 2 electrons =Mg2+ Li
needs to lose 1 electron = Li+1
The reason atoms become ions as well as bond is because all atoms are trying to get 8 electrons in their outer shell. This is called the octet rule. So in the case of sulfur, it needs two electrons to make a complete outer shell, so it will take in two electrons to make the S2- ion. Magnesium on the other hand needs to lose two electrons to make a complete outer shell, so it will give away two electrons and make the Mg2+ ion. Lithium wants to give away one electron so it will make the Li1+ ion.

8. Here is a table showing how the different groups will lose or gain electrons in order to get a full outer shell. Notice all the atoms in a column will give away or take in the same number of electrons and therefore end up with the same charge.

9. Accomplishing the Octet Rule (2 different ways)
1) ionic bonding: (+) ion =cation is attracted to (-) ion=anion
*atom that wants to lose e- will GIVE to atom that needs them
examples: e-
11Na F
1 valence valence
Na = 1 extra e F needs an e-
*Na gives an e- to F octet rule satisfied opposite charges attract
11Na F-
Ionic bond (NaF)- opposite charged ions attracted to each other
Ionic bonding occurs due to the attraction between oppositely charged ions. In this example, sodium (Na) wants to get rid of an electron and fluorine wants to take one in, so sodium gives its electron to fluorine. Once they do this exchange, the sodium ion has a positive charge and the fluorine ion will have a negative charge. These ions will therefore be attracted to each other and that attraction is why they bond.

10. Same as before, only now sodium is donating its electron to chlorine
Same as before, only now sodium is donating its electron to chlorine. Notice that once the different atoms make the exchange, both have a full valence (outermost) shell of electrons and are happy.

13. 2) Covalent bonding- atoms SHARE e- to complete octet(molecule)
Whereas ionic bonding came from the attraction between oppositely charged particles, covalent bonding come from the atoms sharing the electrons between themselves. Neither atom wants to give up electrons, so they end up both using the same electrons to complete their outer shell. In this case, two oxygen atoms each share two electrons with the other so both can have a full outer shell of eight electrons.

14. Same as before only now two hydrogen atoms are each sharing one electron with the other to make a complete outer shell of two electrons.

15. Beryllium sharing with hydrogen and boron sharing with fluorine.

16. e- e- e-
Here is how we can tell what type of bond we have. We find the difference in electronegativity between the two atoms. To do this, find the electronegativites of the two atoms on your periodic table and subtract the smaller one from the larger one. If the difference is less than 0.4, the bond will be nonpolar covalent, if it is between 0.4 and 2.1, the bond will be polar covalent, and if it is greater than 2.1 it will be an ionic bond.
<0.5
05-2.0
>2.0

17. Here we can calculate the difference in electronegativity to discover what type of bond the two atoms will have.
H and O will have a difference of =1.4. This means a polar covalent bond.
C and H will have a difference of =0.4. This means a polar covalent bond.
K and F will have a difference of =3.2. This is an ionic bond.
N and H will have a difference of =0.9. This is a polar covalent bond.
Na and F will have a difference of =3.1. This is an ionic bond.
O and Cl will have a difference of =0.5. This means a polar covalent bond.
<0.5
05-2.0
>2.0

18. Trend in electronegativity as we move down the PT is decreasing, trend as we move left to right is increasing. Fluorine has the highest electronegativity at 4.0.

19. Dark line starting at B and ending between Po and At separates metals and nonmetals. Metals are on the left, nonmetals on the right. A quick rule is if a nonmetal is bonded to a metal, it will be an ionic bond.

21. If two of the same atom are bonded, it will ALWAYS be a nonpolar covalent bond. This is because both have the same pull on the shared electrons, so neither has a larger share.

22. Classify the bond in each of the following as ionic, polar covalent, or nonpolar covalent
KF: Electronegativity for K = 0.8, and F = 4.0;
( = 3.2 ) - [ ionic bond ]
O2 : Electronegativity for O = 3.5;
( = 0 ) - [ nonpolar covalent bond ]
ICl : Electronegativity for I = 2.5, and Cl = 3.0;
( = 0.5 ) - [ polar covalent bond ];
More examples of finding the electronegativity difference.

23. Some Quick General Rules for Bonds
Metal w/ Non-Metal- Ionic
Non-Metal w/ Non-metal- Covalent
Either polar or non-polar, depending on differences in electronegativity.
Same element (Bromine-Bromine) – Non-Polar Covalent
Some quick rules:
Metal w/ nonmetal – Ionic Bond
Nonmetal w/ nonmetal- Covalent, but have to find the electronegativity difference to tell what type of covalent bond.
Same element bonded to itself- Nonpolar covalent.

24. Scientific Process Kind of like investigating a crime Gather Evidence
Make Model
Test Model
Revise Model
When we investigate a crime, first gather evidence, then make a model, then test model to see if it works, gather evidence from the test, then revise the model. This is like Thomson’s model of the atom formed from the evidence of electrons. He saw that electrons existed, so he made the plum pudding model to explain the atom. Rutherford tested this model by shooting alpha particles at gold foil and realized it was incorrect because of the results of the test. This lead him to revise the model. This was then tested and further revised.

25. Work on Ionization Across the Nation Packet
Info on pages 64-65,
Have your Periodic Trends Packet out so I can grade it.

26. Time to be honest with yourself
Come get help if you need it
Should be able to answer all the questions on the review sheet and on my Swift Site
Entry Tasks a great study tool.

27. Learning Targets
I can determine what type of bond two elements will have.
I know the different groups and regions of the periodic table.

28. Homework Ionization Across the Nation
Study for Test- It will be next class
Remember I am here by 7:00 in the morning, every PH, and I stay until at least 3:15 most days.