Significant Figures and Rounding Resources

Here are a few websites that reiterate the work done last class and what we will continue to do in the next day or two

http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch1/sigfigs.html

http://www.purplemath.com/modules/rounding2.htm

http://chemcollective.org/activities/tutorials/stoich/significant_figures


For practice problems go here

http://www.saddleback.edu/faculty/jzoval/worksheets_tutorials/ch1worksheets/worksheet_Sig_Fig_9_11_08.pdf

Lab Write-Up: DIY vs. Store Bought Sunscreen

This lab is due at the end of the day on FRIDAY OCTOBER 9th.  If you get me a copy of your lab by TUESDAY OCTOBER 6th, I will give you feedback.  See the description of the write-up below.

Lab Write-Up

For your FORMAL Lab Write-Up you need the following sections.  Next to the section is a description of the information that goes in it and relative length of each section.

Title: - Should be scientific and not "catchy."  (i.e "Investigating the Effects of Caffeine on Blood Pressure" - - - Not "Does Java Give You the Jitters?")

Introduction:  Usually about 1 page.  It should highlight the scientific concepts needed to understand the lab.  For this lab I would focus on the relationship between energy and EM radiation type, explanation of SPF, and the difference between the active ingredients.  This info should come from your research and needs to be cited.

Materials List:  A list of the materials, chemicals, equipment, etc. you used.

Procedure:  A step-by-step, specific list of the steps you took to collect the data.

Data:  Tables that organize your data.  Highlight UNITS.  Tables should have descriptive titles, especially when more than one is used.  Example:  Blood pressure readings for individuals who consumed varying amounts of caffeine.

Calculations:  Examples of any calculation you used (i.e. averages, percentages, differences, etc.)  As we do more complex labs with different calculation specific to chemistry, this section will change.

Results:  Tables that organize the answers to your calculations.  This section should highlight comparisons to your variables, but focus on the averages and not the individual trial data.

Discussion:  THIS IS NEW.  This section explains to the reader what your results mean.  Which sunscreen was better?  How do you know?  Point out specific results and explain how they lead you to make these decisions.  Is the difference a lot or a little.  This usually takes about 1 or 2 paragraphs.  The next part of the discussion educates the reader on what might have gone wrong during your lab.  This is called sources of error.   Again about a paragraph.  Lastly, the discussion ends with a suggestion to fix the sources of error and/or improve the lab if it was repeated.

Covalent Nomenclature (NAMING)

The big packet (20 pager) linked in the previous post is again useful.  On page 5 is a flow chart on naming ionic compounds that may be helpful.

On page 14 is a summary of today's class where we reasoned through the rules of naming Covalent Molecules.

Page 15 is good practice.

Here is the answer key

Tutorial on Naming Ionic Compounds and Writing Formulas

Tutorials



http://www.csun.edu/~jte35633/chemFlash/compounds.swf

http://www.sophia.org/tutorials/naming-ionic-compounds

http://edtech2.boisestate.edu/lindabennett1/502/Compounds%20and%20Naming/naming%20ionic.html

http://www.kentchemistry.com/links/naming/BinaryIonic.htm

http://www.education.uoit.ca/lordec/ID_LORDEC/ionic_compounds/law_ionic_compounds.swf

Practice Problems - *Note*  You will not need to memorize the list of polyatomic ions, but you will need to be able to use it.  Use the list provided in class to try the practice below.

http://www.mtlsd.org/teachers/smeer/stuff/chemical%20formulas%20all%20worksheets%202011.pdf

The above link contains 20 pages of documents.  I would recommend trying page 13.

Here is a link to my answer key for page 13.  You should not get them all right as we have not covered all of the material yet....

Work for Thursday, September 17th

Before Class on Thursday - 

Email me (one per group)

data table with your data in it (include title)

example of any/all calculations (one example for each different calculation)

results table or other visual representation of your results (i.e.  averages, percentages, differences)

DURING THURSDAY's DAY 2 QUIZ - 

expect questions regarding 

speed of light AGAIN

conversions AGAIN

energy equations ( E=hv)

energy of photons concepts 

procedural questions about the lab (general, everyone should be able to answer)

Work for September 10th

For next class check out the following video

https://www.youtube.com/watch?v=Y0048AI5uEQ

The video deals with the photoelectric effect and the equation E=hv

REMINDER  - Planck's constant = 6.626 X 10^-34 J X Sec

You can also mess with the applet to the right of this blog labeled photoelectric effect.  You need Java to run the program!

You may be ready to try PART2 of the Light-related practice problems