6/7 Scribe Post

Today in class we did the lab practical part of our final exam. When you were waiting to go into the lab to do the lab you were silently studying for the exam after you finished the lab you continued studying. Ms. Heath pulled up a review assignment on the smart board. This is what it said: Review Assignment 1. Cover up the answers on your old tests and try to answer the questions. Ue a system to mark how confident you are in your answer. For example: √ = 90- 100% sure answer is correct * = not sure about the answer ? = random guess 2. Check your answers. Look for patterns in those you got wrong. Write a list of topics from that test you need to review further. Write a list of questions you have. 3. Move on to another test and repeat this pattern. 4. If you need more to do look at your list of review ideas from last class. The last 15 minutes Ms.Heath answered questions about the exam and about any material we were confused about. This is the last scribe post!!!

6/3 Scribe Post

 

Today in class we did not do all that much. We started of with a quiz on Stoichiometry. Then as people finished the quiz we did the Final Exam Lab review, and asked questions if needed. When everyone finished that we went over answers and common questions. The homework is to study for the Final Exam Lab on Monday and to do out last blog comment. To study for the exam look at the sheet of tips she gave us.

Good luck on the exam and have a good summer!!!

6/1 Scribe Post

 

     Hey everyone. So today in class Ms. Heath greeted us and then checked our homework from the previous night which was the stoichiometry worksheet number one. After that we did a warm up on the board. When we were done and after Ms. Heath went over it, we tried some mass-mass problems on the stoichiometry worksheet number two. Then she gave us our homework which is to finish that worksheet for next class. Next we got a worksheet called Applying Stoichiometry: The Airbag Problem. It just talks about how chemistry is in out lives everyday. Sometimes it can even save peoples lives. For example, the airbag. Our homework was to finish the stoichiometry worksheet number two and study for the stoichiometry quiz which is next class. Have a great evening.

I choose…Tinesha for the next scribe.

 

5/27 Scribe Post

Scribe Post

Scribe-Max T.

5/27/10

    We started off today with Ms. Heath giving us our tests to look at and collecting our lab revisions. She also gave us a sample problem to convert from grams to mols. After that, we took out the notes sheet on Stoichiometry we got in out folders. One main idea was that a balanced equation gives the relative number of mols of reactants and products. We then did some sample problems from the note sheet with Ms. Heath. Then we had to do some on our own. We worked on those for the whole class. AT the end of class, Ms. Heath said our homework was to do the Stoichiometry worksheet #1. Then that was the end of class. 

Next Scribe=Jeffrey    

 

5/25 Scribe Post

 

Today, (Tuesday, May 25, 2010) was a relatively untroubled and straightforward day, so if you missed anything, don’t worry about it too much. Well, of course, that means you did miss a test, but we didn’t learn anything new that is too difficult to understand without the guidance of Ms. Heath or fellow students.

 

First off, we started with the test. Everyone, of course, studied really hard, so we all did very, very well.

 

After the test, we worked on a guide/worksheet about “Converting Between Grams and Moles of a Compound.” This may sound very familiar because we have had a lot of experience doing this with single elements and or molecules. The good thing is, it is a very similar process: you define the problem, and use the molar mass of the specific element(s) to convert from moles to grams and or grams to moles using dimensional analysis. “The only thing that is different is that you must calculate the molar mass for a compound.” On the worksheet, there was a given example, but assuming that everyone has the worksheet, I’ll show one of the actual problems (#1):

 

1. How many moles are in 9.4 g of HCl?

 

Defining Problem: 9.4 g HCl = (?) mol HCl

 

Calculating the molar mass for the compound: The molar mass for the two elements that make up the compound (Hydrogen and Chlorine), according to the periodic table, are (rounded): 1.0 g/mol (Hydrogen) and 35.5 g/mol (Chlorine). As you can see, there is one mole of each element.

 

H    1 mol  x 1.0 g/mol = 1.0 g
Cl    1 mol  x 35.5 g/mol = 35.5 g

 

When you add the masses of each element together, you get the total mass, which, in this case is 36.5 g

 

Using dimensional analysis to convert to moles: Since there are 9.4 g of HCl given, you must use this mass and the total mass of the whol compound (36.5 g) in dimensional analysis to convert to moles.

 

9.4 x 1 mol/36.5 g = 0.257 moles of HCl (<- this is your final answer)

 

I hope this example problem was of some help, but keep aware that each individual problem can have two different starting pieces of info. It can either give you the moles and make you figure out the grams of a compound, or the complete opposite, like the problem I did above. Best of Luck! The next scribe is….Max Truman

5/21 Scribe Post

Hayden Lessor What we did in class I’m sorry every one for typing this late, I knew I was going to forget about it…. On the 21 of May, we went over a lot. We first started with handing in our labs, and by the way, it was the most fun one ever. We then took quick notes, we wrote notes about endo= in/inside and therm=heat. Most reactions that us endo and therm, will absorb heat energy. Then we worte about exo= out/outside and therm= heat. Most reactions using exo and therm will releast heat. After we went over notes, we did review sheets. The review was about our up coming test, the test will be about chemical reactions. Then that’s all we did on the 21, we just handed in our labs, went over some quick notes, and reviewed and studied. next scribe will be…. Steven

Homework Hint

Hi all. I know I already asked you to write this hint down the day we started the lab, it is a particularly important one, so I wanted to say it one more time. As you look at reaction number 3, remember, this is the reaction that you may not have been able to predict the correct products for. When writing your final equation, make sure to use the evidence from your observations to decide what products were actually produced. You should find that this reaction actually made 3 products. Two of them you should be able to easily identify based on the different tests you did for gases. The third might be trickier. You should have noticed some water vapor condensing on the inside of the test tube during the reaction, but it may have evaporated quickly.

Finally, as Tram said in her scribe post, remember that observations are an important part of what I’ll be looking at as I grade your lab. Make sure you wrote careful observations of the reactants before you started the reaction, the signs of chemical change you saw during the reaction, and careful observations of the products at the end of the reaction. In the end, make it neat – I want you to really impress me with your work on this one. Don’t forget to go back and check that your predictions reflect any changes we discussed during class. You can always print a new copy of the lab from the website if yours is too messy. Also, I will post it as a word document, so if you prefer to type your final version, the tables, etc. will already be pre-made for you.

Hope these tips are helpful! See you in class tomorrow.   – Ms. Heath