1. Scientific Measurement

2. Using and Expressing Measurements Measurement- a quantity that has both number and unit Scientific notation- using exponents to express really small or large numbers

3. Accuracy and Precision Accuracy- how close a measurements comes to real or accepted value Precision- how close are your measurements to each other Error- experimental value – accepted value

4. More Measure Percent error- (error/accepted value) x 100

5. Significant Figures Significant Figures- included all known value plus one estimated. It insure accuracy. Rules to follow: Every nonzero number is significant Zeros between two non zero numbers are significant Zeros at the beginning of a number are not significant

6. Significant Figures Conti Zeros at the end of the number and to the right of the decimal are significant Zeros that hold place values are not significant Conversion factors do not count for significant figures Rounding- 5 or greater round up, less than 5 do not round

7. More Sig Figs Addition and Subtraction- rounded to the least valued place value Multiplication and Division- limited to the least significant data