Wednesday, January 18, 2012

Dropbox

I love Dropbox.com because it is so easy to put a file in my public folder and then copy a link to it! I also love that every document I saved last night is right at my fingertips this morning with no additional clicks.
See public folder link
Bottom right hand corner of my screen

Tuesday, January 17, 2012

Studying with the TEST in mind: Empirical Formulas

Did you review your polyatomic ions? Please do! Click here to study with quizlet.
Empirical - should make you think of lab or experimental data.  However, empirical formulas are those that are in simplest terms.
*Remember the steps for finding empirical formula:
               1. Find grams. 2. Find moles. 3. Find subscripts. (Compare moles.)

Empirical and Molecular Formula Problems to Practice (with Answers)

Molecular Formulas and % Composition from chemfiesta (with answers)

Brightstorm video of Empirical and Molecular Formulas


These flashcards cover lots of review items as well as our newest vocabulary and problem types.


Friday, January 13, 2012

Chapter 7 Exercise Answers

** 7.11 has been corrected
ODY - Remember that your problem set is due on test day (probably Friday 1/20) and that your work must lead to these answers for credit.  Units must be included. Please slash through units as they cancel. Your work may look different but should lead to the same answer with the same units/sig figs.

Honors - You have begun these exercises. Check the ones you should have completed. We will cover the rest the following week.

7.1 a. 2.0 mol water   d. 2.00 mol carbon dioxide

7.2 a 27 g water         d. 4.04 g molecular hydrogen

7.3 a 67 L Ar             d. 90. L helium

7.4 a 1.25 g/L             d. 0.761 g/L

7.5 44.4 g/mol

7.6 63.8 g/mol

7.7 Ne is twice as fast moving as Kr  (Graham's law is not on this test.)

7.8 a 42.88% C, 57.12% O     b 46.21% Zn, 19.86% Si, 33.93% O    c 3.09% H, 31.60% P, 65.31%O

7.9 45.691% water                           7.10 no calculations just give formula in simplest terms

7.11 a CH2O     b Ca3P2      c Al(ClO4)3

7.12 a  CaCl2     b   CsCl           c Al2S3       d Ni(NO3)2

7.13 C6H6

7.14 C5H10

7.15 C4H10

7.16 C9H8O4

Tuesday, January 10, 2012

Honors Practice Test

Review of Nomenclature Multiple Choice Questions

Honors these are the questions I promised. Odyssey students you could see them as test questions one day as well. Answers are listed if you scroll down far enough.

The essay question requires you to explain nomenclature - make sure you know that molecules generally contain just nonmetals and that we use prefixes to name these. Ex. S0is sulfur dioxide

Class Notes: Formula Calculations

This powerpoint (click the one titled Formula Calculations) is the one I used in class. You can also find it on the assignment page - click on the paperclip.

Here is another link that explains empirical formula from percentage composition.

The trick to chemistry to practice all the problem solving patterns so here is a link to a powerpoint with more examples. And then a worksheet with 3 questions (and answers!) to practice.

Happy Studying!




Tuesday, January 3, 2012

Edmodo

There is a poll on Edmodo that I'd love to see your answers too. It has come to my attention that I left off AP Chem inadvertently...Certainly do want you to consider that one too!!!

You can log in at edmodo.com with the group code you got in class. Parents, I will send home your parent code soon. I'm still figuring out that piece but we certainly want you to be included. This is a facebook like environment without the privacy issues of regular social networking. It targets students and teachers and includes tools like quizzes. I hope it makes school one little bit more fun or less stressful for our students!