Scride Post Nov 22 Per. 5

Monday November 22, 2010

We started chemistry class today by picking up Polarity Olympics: The Games sheets and getting Polarity of Molecules 2 (pg 26) stamped. Before starting the lab we learned that polar molecules are molecules that have both a positive and negative side like water. Also, intermolecular forces are when the attraction is weaker than the bonds that hold it together, but is strong enough to affect the properties of water. We then started the Polarity Olympics lab which had two parts, The Trials and The Games.

The Trials:

Trial 1- The Penny Pile-on: In this trial each liquid will try to create as large a pile on a penny as possible.

Trial 2- The Capillary Tube Climb: In this trial each liquid will try to climb as high as possible in a vertical glass tube.

Trial 3- The Marker Clean Up: In this trial each liquid will try to clean two types of marker from glass.

The Games:

Part 1- Solubility: In this part we each liquid was added to water to see if they would mix.

Part 2- Volatility and Surface Tension: In this part each liquid was ranked in its ability to spread on a table and evaporate.

Homework

Finish Polarity Olympics Lab

Webassigns

Study for Lab Test

Thursday November 18

Yesterday we started the class by picking up pages 21-25 plus another sheet. After picking up the pages, we all sat down for class. Some of the people did not finish building their molecules from two days ago so we then took the time to do that. Mrs. M went around stamping like crazy. After we finished the lab, we did page 20. When we completed 20 we started polar and nonpolar covalent bonding. One of the sheets we got was a periodic tables with a bunch of numbers with the different elements. We got half way through page 21. The rest of it was for homework

Today we started class by picking up 4 pages. After we all settled down we started on the different types of bonds. There are three kinds of bonds; Polar covalent, non-polar covalent and ionic. A polar bond is when one electron has a stronger electronegativity than the other in the bond and holds the electron closer to it's nucleus. Non-polar covalent bonding is when the electron being shared is evenly distributed between the two atoms. An ionic bond is when the pull from one atom is so strong that it rips the electron from an other atom. To find out what kind of bond the molecule has you take the electronegativity of the two atoms and subtract the bigger one from the smaller one. If the difference is less than or equal to 0.4 the bond is non-polar covalent. If the difference is 1.7 or higher the bond is ionic. Anything inbetween those is polar covalent. After learning this we went through and did pages 22-25.

Homework: Page 26 and webassigns & chemthink if you have not finished them

The 16th of November, 2010

Today, in Chemistry 163 Period 5, we began class by getting our previous homework checked (pages 18 and 19, a.k.a. Molecular Shapes 2&3) and stamped. Mrs. M asked us if we needed explanation on anything, and we did a few examples from the pages. (For answers, please refer to the photos...sorry if quality is bad. Remember: you do have the VSEPR sheet to refer to for more answers!)

page 18:

page 19:

After that, we continued on to our next activity: Molecular

Geometry - the three-dimensional arrangement of the atoms that constitute a molecule. We used the packet that consisted of rows of molecules and columns of the Lewis Structure, # of Atoms on central (refer to the gold VSEPR sheet for the #/#/# answers), # of Lone pairs, Shape, 3D Picture, and Stamp (from Mrs. M).

ex.

We used wooden spheres, sticks, and springs to create 3D molecules during class. If you did not finish or get them all checked, please finish the work tonight for homework, and we will have time in class tomorrow to finish creating them. Enjoy the late arrival tomorrow! But do your homework!

HOMEWORK:

• finish Molecular Geometry packet
• ^remember to answer the questions on the 2nd page!
• ENJOY THE LATE ARRIVAL

Sorry Mrs. M for getting you off track with the Scribe Posts-- it won't happen again.

Kiva T.

Lewis Structures – November 9th 2010

      When we first walked into class today, we picked up pages 9-15. Then, Mrs. M stamped our page #6 (the homework assigned yesterday). Once everyone was settled again, we went over all the answers to page 6. These answers can be found on Moodle!

                  WARNING!: Tomorrow is the beginning of a streak of 6 quizzes! The quiz tomorrow will be seeing if you can tell the difference between and Ionic and Covalent compound, and if you can name each of them.                  

                 

Ionic	Makes compounds	Transfers electrons	Made with metals and nonmetals	Positive and negative charges	Weak bonds!!	Ex: NaCl
Covalent	Makes molecules	Shares electrons to be noble	Made of ONLY nonmetals	Neutral charges	Strong bonds!!!	Ex: H₂O

                  Next, we did pages 7, 8, 10, & 11. You may read page 9 at your own leisure, as it only describes how to create a Lewis structure. Mrs. M knows 2 ways to figure out how to create Lewis Structures. She began to teach us the first way, (described on page 9) and the taught us “her way”. On our periodic tables, we added the amount of valance electrons. Under the first family we put 1, indicating there is 1 valance electron on all the above atoms. 2^nd family we put 2, 13^th we put 3, 14^th we put 4, 15^th we put 5, 16^th we put 6, 17^th we put 7, and 18^th we put 8, indicating that these atoms are stable.

                  GUIDELINES OF LEWIS STRUCTUES:

                  -Consult the molecular formula and sum up all the valence electrons from the separate atoms.

                  - Choose central atom

                  - The first element in the compound becomes the central atom (excluding hydrogen).

                  -Insert pairs of electrons between all pairs of atoms that are to be bonded together

                  -Place any remaining electrons on peripheral atoms as unshared pairs, starting with the most                   electronegative such atom.

Mrs. M began teaching us “her way” of drawing Lewis Structures. This method includes NHS (Needed; Have; and Shared electrons.)

                  First you take the amount of atoms in the compound (excluding Hydrogen) and multiply                   it by 8 electrons which results in the amount of electrons NEEDED to have a stable compound.

                  Then, you fine the amount of valance electrons you have. Look at the charge of the atom that we listed at the bottom of the periodic table and add them all up to equal the amount of electrons you have in that particular compound.

                  Lastly, you subtract the amount of electrons you have from the amount needed. This resulting number is the amount of electrons that need to be shared between the atoms.

FOR EXAMPLE: (done in class)

                  Take the compound NF₃. The amount of atoms in this compound is 3. 1 Nitrogen and 3 Fluorine’s. You multiply 4 by 8 to get the amount of electrons needed to create a stable compound.

4 x 8 = 32

                  Next you find the amount of electrons you have. There are 5 valance electrons in Nitrogen, and 7 in Fluorine. Remember, there are 3 Fluorine atoms!!! Add all the valance electrons together to get the amount of electrons there are.

5 + 7 + 7 + 7 = 26

                  Finally, you would subtract 26 from 32 to find the shared electrons.

32 – 26 = 6 electrons

                  Since N is the first atom used, it would become the central atom. You write N in the middle of the space provided. There are 3 fluorine atoms so you draw 3 F’s on 3 sides of the N. Because there are 6 electrons being shared, you draw a line from the N to each F. Each atom needs 8 total electrons to become stable. To show the addition of the last 2 atoms to N, you would put 2 dots on the last side unoccupied by the lines. Finally, you need to make each F atom stable. You add 2 dots on each side left on the F, to create 8 electrons on each atom.

                  HOMEWORK! Finish the 2^nd column of page 11.

Annika S

Monday November 8th. Covalent Bonds.

   Today as we walked into class we were greeted by 8 new sheets to add to our notebooks. They are about Covalent Bonding. If you weren't here (or just forget) last Friday we were in the Math Lab doing the covalent bonding Chemthink. We also have 2 Webassigns due November 24th on Covalent Bonding (Chapeter 5). 

  During class we completed pages 2-5 of our new sheets. Page 1 is optional extra credit for which you have to go back to the Chemthink and get your answers from that. If you were absent the answers for pages 2-5 are as follows:

Pg. 2:

1. a) decrease, increase, P-e-1 attraction. Attraction=bonding=stability

    b) increases, decreases, P-P repulsion. Repulsion=longer bond=less stable

Pg. 3:

2. inversely, increase, decrease

3. a) increases as it goes down the periodic table and decreases as it goes across. 

    b) increases as it goes down because as you add more shielding electrons there is a weaker pull from the nucleus.

Pg. 4: 

-write the 1st element

   *add the appropriate prefix with the exception of mono

-write the name of the second element 

   *drop ending and add -ide

   *add appropriate prefix

dinitrogen pentoxide: N2O5

carbon tetrachloride: CCl4

nitrogen dioxide: NO2

sulfur dioxide: SO2

phosphorus pentaflouride: PF5

nitrogen monoxide: NO

sulfur trioxide: SO3

nitrogen triflouride: NF3

boron trisulfide: BS3

carbon dioxide: CO2

nirtogen triiodide: NI3

carbon tetrabromide: CBr4

Pg. 5:

1. NaO3.....I......sodium nitrate

2. Al2O3.....I......aluminum oxide

3. PCl5.....C......phosphorus pentachloride

4. IF3....C.....iodine triflouride

5. LiOH.....I....lithium hydroxide

6. Ba(NO3)2.....I.....barium nitrate

7. SrBr2......I.......strontium bromide

8. Cu2S......I....copper (I) sulfide

9. N2O5.......C.......dinitrogen pentoxide

10. Fe3N2.....I......iron (II) nitride

11. CO......C......carbon monoxide

We also went over the Ionic Bonding Quest in class today. Remember to take it if you haven't already and if you have questions see Mrs. M. 

Again, Homework:

Webassigns (November 24th)

Page 6 (November 9th/tomorrow)

Page 1 (Extra Credit) (November 9th/tomorrow)

Reviewing

On Tuesday, November 2nd, wewent over a quick review on Ionic Bonding and then proceeded to learn/review how to name Ionic Compounds. The process is as follows:

• Write the name of the cation(positive metal ion)

• Write the name of the antion (negative non-metal ion)

- Drop the ending and add -ide* (ex: calcium Chloride)

*If a polyatomic ion is formed, look up the name. (ex: NaNO3= Sodium Nitrate)

*If transition metals are involved, determine the amount of electrons lost, and use roman numerals to indicate the charge in the name (ex:FeCl2= Iron (II) Chloride)

We then proceeded to finish the third column of the table on pages 7 and 8, and then we worked on pages 11, 12, 13, and 14 in our composition notebooks as a class. As we did not get to finish page 14, it was assigned as homework, along with our Webassigns and the Chemthink. As a reminder, we have a Quest on this unit on Thursday.

Ionic Bonding

We started class by collecting some worksheets at the front table. The worksheets were pages 9, 10, and 11. Mrs. Mandarino also gave us new Periodic Tables that have new information on them that should be helpful to us. REMINDER. SCRIBE POST ARE GRADED, SO IF THEY ARE ASSIGNED, PLEASE DO THEM. After that, we went over Thursday's homework (worksheet pages 4 and 5). Not many people did the homework though, so Mrs. Mandarino stamped it for extra credit. Pages 4 and 5 were about Ionic Formulas and Forming Ionic Compounds.
Ionic Formulas:
We went over how to make a formula based from a pair of Ions.
Ex. K+ and O2-
There are three ways to do this, Common Sense, Common Denominator and Criss-Cross.
Essentially, K+ and O2- will become K2O

REMINDER. PROTONS ALWAYS STAY THE SAME. THEY NEVER CHANGE.

We are always trying to pair up the ions so that they will be neutral.
If there are a group of ions and you need to choose which should go together, choose the two that will have opposite charges and will "cancel" each other out.
Ex. Na+ S2-, I-, Zn2+
Na+ and I- should go together because one ion has a +1 charge while the other has -1 charge. Their opposite charges will cancel each other out (which is our goal).

After we went over the homework/extra credit, we (as a class) did pages 6 and 7 together.
6 was also about forming ionic compounds, but 7 was about Polyatomic Ions.

Polyatomic Ions

• Poly=Many
• Atomic=Atom
• Ions made up of many atoms
• ex: NO3 -1
• There are many negative Polyatomic Ions bu only one positive Polyatomic Ion.
• NH4 +1

Polyatomic Ions are always written in a specific order. The positive part is written first and then the negative part is after.

Cation: Positive Ion. You can remember this by the t in cation. The t looks like a + for positive.

Anion: Negative Ion. You can remember this by the n in anion. N stands for negative.

Also, the new periodic tables that we metioned before have names of some polyatomic ions which is the updated part.

The homework was the rest of page 7 and page 8. For the homework, we haven't learned the names part yet, so that part doesn't need to be done. As always webassign is homework.

Have a good weekend and Happy Halloween!!