1. Significant Figures Definition: Measurement with Sig Figs:
Digits in a measurement that have meaning relative to the equipment being used.
Digits that can be known precisely plus a last digit that must be estimated.
Depends on the equipment being used to measure.

2. Significant Figures Pacific to Atlantic Rule Decimal Present
Start from Pacific, every digit beginning w/ first non-zero digit is significant
How many sig figs?
20.0g cl
1000. cm

3. Significant Figures Decimal Absent
Atlantic to Pacific Rule
Decimal Absent
Start from Atlantic, every digit beginning with a nonzero digit is significant.
How many sig figs?
100020g
1000g
13250g

4. Measurement Notes – Sig Figs
Calculations using Sig Figs
Addition/Subtraction
Example:
Multiplication/
Division
Example
Limit and round to the least precise place
123.25mL mL mL =
Limit and round to the least # of significant figures.
23.0cm x 432cm x19cm =