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.

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 0.000568cl 1000. cm

Significant Figures

Atlantic to Pacific Rule Decimal Absent Start from Atlantic,

every digit beginning with a nonzero digit is significant.

How many sig figs?100020g1000g13250g

Measurement Notes – Sig FigsCalculations using

Sig FigsAddition/Subtraction

Example:

Multiplication/Division

Example

Limit and round to the least precise place

123.25mL + 46.0mL +86.257mL =

Limit and round to the least # of significant figures.

23.0cm x 432cm x19cm =