My daughter’s not feeling well, so I will be staying home with her on 2/23/2010 (Tuesday).  Here’s how that will impact your classes.

CHM 100:  My absence shouldn’t have any effect on your class; I anticipate being back on campus tomorrow morning for class.  Quiz #4 is due tomorrow (2/24/2010).

CHM 110:  We’ll miss class today.  I had intended to cover molarity and the information you’d need to know to finish experiment 4C today in class, but we won’t have the opportunity.  So, we will slide the lab schedule back a bit to give us an opportunity to catch up.  We won’t meet CHM 110 lab this week, and will perform experiment 4C next week (3/3 and 3/4).  I will update the lab schedule to reflect this change.  The write-up for experiment 3B will be due when you come to lab to perform experiment 4C.

CHM 111:  We’ll miss class and today’s lab.  The Monday lab section will continue on their schedule like normal.  The Tuesday lab section will perform part 1 of the gravimetric chloride lab next week, and will finish part 2 of the lab on 3/9 along with the freezing point lab (there should be enough time to do part 2  at the beginning of the freezing point lab.)

Here’s the shared data from CHM 110 Experiment 3B. These are the ratios of mass product / mass barium chloride dihydrate that you need to complete the table on page 74 and answer the questions on pages 75 and 76.  This is data for the Wednesday lab section (section 2)!

Ratio of (mass product / mass BaCl₂.2H₂O):

• 0.89152
• 0.84770
• 0.84425
• 0.84847

The write-up for Experiment 3B is due at our next lab meeting. If you have any questions about either the calculations or the rest of the write-up, either come by my office or ask here in comments.

Here’s a handout that describes the calculation procedure for this experiment:

[CHM 110 Experiment 3B calculation notes]

I recommend that you use your TI-83 calculator or a spreadsheet to find the standard deviation the lab manual asks you to calculate.