by horse Comment Closed

LARN 068 C17D4

Start the following in class:

1. In your Journal Notebook write your journal entry on sheets of three holed 8.5 inch by 11 inch ruled paper.

  • In the upper right corner white space of each upward facing page, use a blue or black pen to write your hand in number within a circle followed by your name. 
  • To the left of the marginal line, print J68A and circle it.
  • Each journal entry should either be at least a paragraph of exemplary writing and penmanship concerning a single topic, or be a concept map relating chemistry terms. Begin each day’s paragraph with a topic sentence, follow with explained instances, and close with a focused summary statement.
  • The required journal focus topic J68A for today is:

a. Describe similarities between compounds that form molecules and compounds that are network solids.  Use examples in your explanation.  Be sure that you explain how each example demonstrates the concept being considered.

b. Describe differences between compounds that form molecules and compounds that are network solids.  Use examples in your explanation.  Be sure that you explain how each example demonstrates the concept being considered.

2.  An electron group is either a single covalent bond, a double covalent bond, a triple covalent bond, or a non-bonding electron cloud of one or two electrons.

The second required journal task J68B is to copy the following table into your journal notebook and correctly fill in the five (5) columns that contain spaces.

a. For each compound listed in the table below, enter the approximate measure of the central bond angle of the substance’s molecules predicted in our recent model building laboratory activity.

b. Look up the experimentally determined, actual measure of the bond angle  in the reference table given below this one, and enter the experimentally determined actual value of the central bond angle in the first table.

c. Compute the discrepancy of each simple predicted value for the central bond angle from its actual value.

        d. Compute the percent discrepancy of each simple predicted value for the central bond angle from its actual value.

  Compound Dash/dot formula for the molecule

Hint: Use TE, VE, SE, NBE method or refer to examples in the current text

 Number of electron groups (number of single, double, and triple bonds + number of nonbonding pairs) around central atom; steric number Coordination number of the central atom Number of nonbonding electron pairs on the central atom Geometry of the Molecule Predicted Measure in degrees of the Central Bond Angle from the Dash/dot Model Type of Hybrid  Atomic Orbital on the Central Atom that could account for the measure of the central bond angle Experimentally measured Bond Angle  in degrees    (from published research data) Discrepancy of the Predicted Bond Angle from the Measured Bond Angle Percent  Discrepancy of the Predicted from the Measured Bond Angle
HCl 4 1 3 linear   NA  NA   NA   NA
H2O 4 2 2 bent 104.5°    
NH3 4 3 1 trigonal pyramidal 107.5°    
CH4 4 4 0 tetrahedral 109.47°    
CO2 2 2 0 linear 180°    
SO2 3 2 1 sulfur dioxide 119°    
H2CO 3 3 0 trigonal planar 124°    
SO3 3 3 0 trigonal planar 120°    

3.  The third required journal entry topic J68C, is

How does the number of electron groups attached to a central positive kernel together with the number of atoms bonded to the central atom determine the bond angle formed from a line segment drawn through the center of an electron group to a central kernel and from there to the center of another electron group?

Recommended for those who have time left in their 45 minute study period, but not required of all:

1. Different classes are in different places in doing the laboratory activity in which you are to build and examine three dimensional models of covalent molecules. If you have fallen behind the place where your teacher expects you to be, you need to catch up by constructing each framework model for lab activity U05-5 (A28LA), showing it to your teacher for feedback, and fixing anything up on your formulas and observations sheet that was suggested.  The process is described in more detail in HLARN 067.

If you predicted Column 6 from your dash/dot formula in Column 5, when you get to class start with the substance named in row one and put together a model for a molecule of each of the 15 substances in such a way that the model represents that  dash/dot structure given in Column 5. 

Each person must bring each model and its description on the observation sheet to your teacher and listen to and heed any suggestions that your teacher makes before beginning the Analysis and Conclusions section of this laboratory activity.

After you have shown all your two and three dimensional models to your teacher and have received his ink mark on each one, use full sentences to write accurate responses to the three Analysis questions.  Read each question carefully and make sure that you understand what is being asked before fashioning your well thought out and expressed responses to the questions.

To word process your Analysis, Conclusions, and References sections using the template for U05-5,  locate it at Google Drive > Student Resources > Laboratory Activities > Honors Chemistry Guided Inquiries, make a copy of it, download it, and rename it as described in the instructions given below.

For your Conclusions, go on and clearly state each original Problem question and the evidence and reasoning in support of your response to each Problem question. Be sure to offer a thorough discussion of each Problem question that leads up to your stated answer in each case.

    • Save your laboratory report to your MNSD Google drive for easy access at school in the Lastname_First name_LaboratoryReference Designation LaboratoryInvestigationName format.  Also save your file to your chemistry flash drive and put the flash drive in your zippered, grommeted pencil case that you take to school.
    • Peer review
      • Once the laboratory report has been completed, print off a copy of it. Submit the report to a fellow student for him/her to note in purple ink whether the report has any omissions, simple mistakes or oversights, deficiencies or other problems that need to be rectified before submission to the teacher for assessment. After the notebook or laboratory report is returned to you, improve your report in any area marked by your peer for your supplementation, editing or revising, and then review your report yourself to make sure that you have clearly expressed what you desired to express in each section of the report.
    •  Peer reviewer’s signature in purple ink
      • After using a rubric and the RACES* mnemonic to check the laboratory notebook and laboratory report, the peer reviewer should sign his/her name in purple ink below the other information given in the heading on the first page of the laboratory notebook and laboratory report.  Without being peer reviewed a report does not qualify for top level evaluation.
    • After you are satisfied that you have prepared your best work, resave your report and upload your saved word processed Analysis and Conclusions and Reference section of your laboratory report to your chemistry class’ account at  http://www.turnitin.com before the due date.   To join your chemistry class, first obtain your class’ enrollment key from your teacher and follow the instructions at How to Set Up and Use a Turnitin Account .
  • You also need to turn in a complete paper copy of your laboratory report to your teacher.  Any hand written pages need to be stapled together in page number order with the Analysis, Conclusion, and Reference sections that you were required to word process and print out.  Include all eight (8) pages of the original handout including your teacher signed hand written “Results” pages containing your dot, dash/dot, model sketch, and polarity of molecule analysis.
  • Personally hand in your completed laboratory report to your teacher.  If your class does not meet on the due date, stop by before or after school or between classes to turn in your report so that you get your report in on time.  For all Guided Inquiry reports, print off a copy of the conclusion and attach it to your written laboratory report before you hand it in.