1. Significant Figures in Calculations
Determining the Density of Graphite

2. Multiplication & Division Significant Figures
The calculation result has the same number of significant figures as the measurement with the fewest significant figures.
3.56 cm
Width 
5.425 cm
Length
Area =
Length
Width
4 Sig. Figs.
3 Sig. Figs. 
Area =
5.425 cm
3.56 cm
3 Sig. Figs.
Area = cm2
Area = cm2
(3 Sig. Figs.)

3. Addition & Subtraction Decimal Digits
The calculation result has the same number of decimal digits as the measurement with the fewest decimal digits. cm
2 decimal digits cm
3 decimal digits cm
2 decimal digits
Answer: cm

4. Density
Density: Measure of the amount of mass contained in a specific volume.
High Density: Large mass in small volume.
Low Density: Small mass in Large volume.
Low density materials float on high density materials.

5. Density: Calculated Mass Density (D) = Volume
Graphite: One of three solid forms of pure carbon.
Mass
Density
(D) =
Volume

6. Graphite: Mass Measurement
Massgraphite = g
4 Sig. Figs.

7. Graphite: Volume Measurement
Graduated Cylinder: After
1 Decimal Digit
112.2 mL
103.0 mL -
9.2 mL
Water Displacement
1 Decimal Digit
Graduated Cylinder: Before
Volume graphite = 9.2 mL

8. Density Calculation Massgraphite = 23.01 g Density = Mass Volume (D)
Volume graphite = mL
Density =
Mass
Volume
(D)
4 Sig. Figs.
23.01 g
Density =
(D) =
9.2 mL
2 Sig. Figs.
2 Sig. Figs.
Density =
(D)
2.5
g/mL

9. Better Measurements? Volume graphite = 9.2 mL Massgraphite = 22.9991 g
Density =
Mass
Volume
(D)
6 Sig. Figs. g
Density =
(D) =
g/mL
9.2 mL
2 Sig. Figs.
2 Sig. Figs.
Density =
(D)
2.5 g/mL
No improvement since the volume measurement limits the answer’s significant figures.