9/3/2013

6 Handouts were passed out today.
 http://gbs-moodle.glenbrook225.org/moodle/file.php/12015/1314_Unit_1/Unit_1_Handouts/9.3_Sci_Notation_and_Sig_Figs_Practice.pdf

http://gbs-moodle.glenbrook225.org/moodle/file.php/12015/1314_Unit_1/Unit_1_Handouts/9.3_Alien_Unit_Conversions_Ws.pdf

http://gbs-moodle.glenbrook225.org/moodle/file.php/12015/1314_Unit_1/Unit_1_Notes/9.3_Notes_on_Measurements_and_Sig_Figs.pdf  (last 4 pages)

One volume measurement sheet

Hw: Metric Conversions Practice check (answers checked in class):

1. 100 cm
2.  0.072 dm
3. 1,000,000 mm
4. 2 mm
5. 0.094 L
6. 101,000 cm
7. 0.000721 km
8. 0.0052 kg
9. 0.071 dg
10. 5.0 cm(3)

Questions For Today:

Remember accuracy and precision?

How do they relate to lab equipment? what is certainty in measurement?

What are significant figures? what rules go with them?

Remember scientific notation?

How can I do a conversion if I can’t just shift the decimal? What is dimensional analysis?

Class Work:  

How to measure the volume in a graduated cylinder and beaker (worksheet notes)

round bubble = meniscus ---- check the bottom of the bubble to measure the volume

Can i trust the volume? you can because of the markings on the instrument

 We are guessing the volume because it is unsure
        Ex: If the measurement is between 8.6 and 8.7, it can be measured as 8.65 mL with the 5 being a guess

Burets are read from the top to the bottom

Measurements and Uncertainty worksheet was done with a partner:

2.25 cm
0.75 dm
34.0 mm
20.7 cm
12.8 cm
30.0 mL
28.5 mL
32 mL

We went over the notes on the Powerpoint (link above)

These calculations aren't done through memorizing, but they are to be practiced.

Next Scribe: Carrie Reusche