1. SCIENTIFIC MEASUREMENT

2. QUALitative Measurements
descriptive, non-numeric results:
hot / cold heavy / light etc.
often influenced by the measurer’s perception

3. QUANTitative Measurements
definite results – typically numbers with units:
100 °C 32 °F
30 mL g/cm3

4. QUANTitative Measurements
definite results – typically numbers with units:
only as accurate as the instrument and method used to measure

5. Accuracy and Precision
accuracy - how close your measurement is to the true value
precision - how close values in a series of measurements are to one another

6. Significant Figures
Math: exact numbers 1 = 1.00 = Science: numbers are measured data – limited in the number of usable digits, or significant figures

7. Significant Figures
The sig figs in a measurement include all the known digits, plus one last digit that is estimated.
When doing a calculation, the sig figs in the answer depend on the sig figs used in the calculation.

8. Significant Figures: Rules
Every non-zero digit is significant.
Zeros between non-zero digits are significant.
ex: 2008
15.08

9. Significant Figures: Rules
Zeros in front of significant digits are not significant.
ex: 0.04

10. Significant Figures: Rules
Zeros at the end of a number & after a decimal pt are significant.
Zeros at the end of a number without a decimal point are not significant.
ex: 690,
14.00

11. Significant Figures: Rules
Exact or counted numbers have unlimited significant figures.
ex: number of students in class
number of eggs in a dozen
12 eggs, or … to infinity

12. Significant Figures: Rules