1. Check wall for updated grades as of midnight
Check wall for updated grades as of midnight! ELEMENT QUIZ #2 tmrw Density HW (front & back) due tmrw
Put page 28 on your density handout.
Start a page 27 Cornell Notes:
TOPIC: DENSITY
OBJ: Manipulate chemical quantities using scientific conventions.
ESQ: How can slope determine density of an object?

2. Density Density: ratio of mass to volume
characteristic property that depends on the composition of a substance
does not depend on the size of the sample  intensive physical property
Intensive Extensive
Color Length
Boiling Point # of atoms
Phase of matter (S, L, G) Mass

3. Density Column
Smallest Density
Increasing Density
Largest Density

4. Density Column Practice!!
Four liquids were placed in a graduated cylinder and they formed 4 layers – use colored pencils to color in the layers formed
Five objects were then dropped into the density column. --Draw the objects on your column.
Color
Density (g/mL)
Red
1.00
Green
0.75
Blue
1.10
Orange
1.25
Object
Density (g/mL)
2.75
1.04
0.9
0.65

5. Equation D = m V D: density (g/mL or g/cm3) m: mass (g)
V: volume (mL or cm3) D = m V

6. Example #1
What is the density of a material that has a mass of 15 g and a volume of 3 mL?

7. Example #2
What is the mass of an object if its density is 2 g/cm3 and its volume is 5 cm3?

8. Example #3
What is the volume of a liquid with a density of 2.0 g/mL and a mass of 8 g?

9. Think about this, genius!!
A sample of water has a mass of 10.0 g and a volume of 10.0 mL
10.0 g
D =
10.0 g / 10.0 mL
m = _______
10.0 mL
V = _______
D = 1.00 g/mL

10. Example #4 Half of the water is removed.
Predict what will happen to the density.

11. Terrific Tuesday Check wall for updated grades as of midnight!
Get out density HW page
Get out new piece of blank paper
Use the ziploc of elements to quiz your table!
ELEMENT QUIZ #2 tmrw
Density HW (front & back) due tmrw
PINK OUT PEP RALLY FRIDAY FOR S’MORES!!!

12. Percent Error Relative error equation Actual - Theoretical
Absolute value (no negatives allowed)
Percent Error = Experimental - Acceptedx 100
Accepted
Theoretical

13. Let’s calculate the % error of a lab group that measured the dimensions for steel.
The calculated values of the steel were: Mass of sample: g Length of sample: 2.26 cm Width of sample: 1.80 cm Height of sample: 2.41 cm The true value for the density of steel is 7.8 g/cm3.

14. Percent Error = Experimental - Acceptedx 100%

15. Page 29 – Density Mini-Lab
Section 1 (top ½ of page)
Determine density of 5 liquids and 2 solids using tools provided on side counter
Chemicals on back table – they stay put!!!
No more than 10 mL of each liquid
Section 2 (bottom ½ of page)
Draw two 100 mL graduated
cylinders
Left  prediction
Right  actual experiment
ACTUAL
PREDICTION