Thursday April 28th

Todays beautifully short class began with going over the right column of page 5 in the packet. Mr. H. highlighted the water dissociation equation and the fact that the equilibrium of the ions is always 1.0e-14. Also that neutral solutions have equal ion concentrations, acidic solutions have more hydrogen ions, and basic solutions are just written differently and OH dominates. On the back side Mr. H. noted that when discussing powers of ions it really was just referring to the numerical value of the exponent. Below we were introduced to equations we would be using on page 6.

Next we flipped back to page 5. Mr. H. briefly spoke about number 11 which has some useful equations. He also mentioned that on a previous reading webassign there was a study tip regarding those equations:

STUDY TIP:
On a note card, write down the equations/formulas presented in these two sections of reading; these include Equation 13.1, Equation 13.2, Equation 13.3, the equation on the line below Equation 13.3, Equation 13.4, and the first equation on page 356. Keep the note card handy during class, when doing homework and when on FaceBook. Accept it as your friend.

^^^YOU HAVE BEEN WARNED

On page 6 we went over some of the table for number 12. We were able to solve columns 1 and 2 by dividing 1.0e-14 by the given OH or H3O value. The answers were for row1: 1.0e-12 row2: 1.0e-11 row5: 1.0e-7 row6: 2.0e-14 row7: 1.67e-15 row8: 2.5e-15. Next we were easily able to do columns 3 and 4 for 3 and 4. Because the pH and pOH values have to equal 14 row3: 9.00 row4: 3.00. We were also able to do column 3 and 4 for rows 1 and 2. Using our calculator we used the equations from page 26. For row 1 we took the negative log of .o1 with a base of 10 and got 2.00 for pH and 12.00 for pOH. Therefore we knew it was acidic because the pH was less then 7. For row 2 we got 3.00 for pH and 11.00 for pOH and for row 6 we got 13.7 for pH and .3 for pOH. Therefore rows 1, 2, 3, and 4 are acidic and row 6 is basic. That was the end of class.

Thursday, September 2, 2010

Today was a rather average day in Chemistry Class. Mr. Henderson began by taking attendance and then going over the blog post done by Dmitriy from the previous day. Mr. Henderson then explained our homework due Tuesday more thoroughly. The homework was a 1.1 WebAssign on the Classifications of Matter. Mr. Henderson explained how the questions worked and how for some questions you received multiple chances to get them correct.

We then moved on to pages 1 and 2 in our Unit 1 packets. Page 1 and the first half of page 2 were about the symbolic language of mixtures. For the first group we were given a drawing of a substance and asked how many types of atoms were in it and how many types of compounds were in it. Then in part 2 we were given a diagram of the substance, and the symbol for it. We were then asked to describe the substance using words like atom, compound, molecule, element, etc...

The bottom half of page 2 was about the interpretation of mixtures. We were given long symbols for a substance and were asked how maybe elements and compounds there were, as well as the total number of atoms and the total number of molecules. This part was the most difficult for the class to understand.

We finished class up with Lab MM3 or the Salt, Sand, and Iron Lab. The purpose of the lab was to distinguish between salt, sand, and iron on the basis of their physical characteristics. We began by just observing the three substances and recording their color, granular size, and texture. Next we tested each of the item's magnetic properties by moving a magnet over each and seeing how it reacted. My lab group discovered that only iron had magnetic properties and that they were very strong. Next we tested the solubility in water of each substance by adding a little bit of each to a test tube of water and mixing it around. My group found that only salt dissolved in the water and the other two just sunk to the bottom.

Class today was very fun and very educational. The lab was a great way to test properties and it was great to have more practice on the types of matter.