1. Warm-up (Sept 19 and 20) Find your new seats!
Please get out a pencil and keep everything else away.

2. Image: http://morrisonlabs.com/lab_safety.htm
What’s wrong? In your groups, identify 6 different safety concerns shown in the picture below.
Image:

3. The answers are … Don’t fool around during a lab.
Always wear safety goggles when doing an experiment and DON’T EVER SIT
Always point test tubes and other items away from yourself and others when heating.
Don’t eat or drink while in the lab.
Keep hair and other flammable objects away from flames.
Don’t leave a flame unattended.
Image:

4. Safety Quiz Time!
When you are done, please raise your hand and I will come get the quiz.

5. Sig Figs Help! We are having some serious trouble still with Sig Figs!
See extra practice folder on Moodle and HW 3 and HW 4 keys
Also Khan Academy videos linked on Moodle – USE YOUR RESOURCES
Come see me today at lunch (T or Th)!
Quiz in two classes on Sig Figs and elements!

6. Density: an intensive physical property
Density (ρ) = mass (g)
volume (mL or cm3 or cc)
Which is more dense?
Hammers (the mass is more compact into a smaller volume)
10 kg of feathers?
OR 10 kg of hammers?

7. Calculations in Chemistry!
Required Format For All Lab Calculations:
LABEL, SHOW EQUATION, SHOW MATH
Label:
Show Formula:
Show work: (sig figs and units!)
Density example in notes

8. Calculations in Chemistry! (A finished example for you)
Required Format Reminder:
LABEL, SHOW EQUATION, SHOW MATH
Total mass of two washers
Formula:
Total mass of washer = Washer 1 + Washer 2
Show work:
Total mass = g g = g

9. How can we measure density in lab?
Of a box?
Of a hammer?
BOX. Ruler and balance
Hammer: Balance, but ruler doesn’t work for oddly shaped object! You have to use volume displacement!

10. Volume Displacement
A way to measure odd-shaped items in lab using water and a graduated cylinder!
What will be the data you need for this calculation?
What will be the formula for this calculation?

11. Measurement 101
How long is the apple in centimeters? cm

12. Measurement 101 How much liquid is in the graduated cylinder in mL?

13. Set up Lab book
Table of Contents!

14. Lab #1 – Density (Part 1) – 20 min
READ the handout carefully NOW
Three trials of each cylinder
Test one NUMBER and one LETTER
Be good scientists!!
What is the correct data table to have for this lab (on boards)??
Part 1 Calculations DUE: Next class!
Hand written in Lab books, using proper format we learned today.
Give 5 min to read, then do data table together in lab books

15. Homework Day 6 Sig Figs and periodic table quiz 2 M/T
Part 1 Calculations DUE: Next class!
Hand written in Lab books, using proper format we learned today.