2. Significant Figures “SIG FIGS”

3. What are Significant Figures? In science we say that significant figures are the figures (#’s) in a measurement that consist of all of the numbers known plus one # which is somewhat uncertain or estimated.

4. What measurement is represented in the diagram? 2.35 cm How many “sig figs”? 3

5. Rules for Sig Figs All non zero numbers are Significant. –Ex. 45.87 4 significant figures

6. Numbers with zeros Zeros appearing between non-zero numbers are significant. –Ex: 70894 sig figs Zeros to the LEFT of a number are NOT SIGNIFICANT. (they are just placeholders) Ex. 0.0003783 sig figs Zeros at the end of a number and to the right of a decimal point are significant. Ex. 7.5004 sig figs

7. Zero rules cont. Zeros at the end of a measurement are questionable. Ex: 100. 3 sig figs Ex: 100? Ask the source If there is no decimal at the end assume that the zeros are NOT significant

8. Try a few examples