 # Significant Figures. 1.All nonzero digits are significant. Example: 145 (3 sig figs) 2.Zeroes between two significant figures are themselves significant.

## Presentation on theme: "Significant Figures. 1.All nonzero digits are significant. Example: 145 (3 sig figs) 2.Zeroes between two significant figures are themselves significant."— Presentation transcript:

Significant Figures

1.All nonzero digits are significant. Example: 145 (3 sig figs) 2.Zeroes between two significant figures are themselves significant. Example: 301 (3 sig figs) but 310 (2 sig figs) 3.Zeroes at the beginning of a number are never significant. –Example: 0.692 (3 sig figs) 4.Zeroes at the end of a number are significant if a decimal point is written in the number. Example:1050 (3 sig figs) Example: 4.7010 (5 sig figs)

Calculating with Significant Figures When addition or subtraction is performed, answers are rounded to the least significant decimal place. Example 1: 16.9 + 210 = Answer is NOT: 226.9 Answer is: 230 Example 2: 134 – 1.99 = Answer is NOT: 132.01 Answer is: 132

Calculating with Significant Figures When multiplication or division is performed, answers are rounded to the number of digits that corresponds to the least number of significant figures in any of the numbers used in the calculation. Example 1: 125.0 x.014 = Answer is NOT: 1.75 Answer is: 1.8 Example 2: 5.49 / 5 = Answer is NOT: 1.098 Answer is: 1

Density Density = mass / volume –What is the density of a metal that has a mass of 5.0 g and a volume of 30.0 mL? 0.17 g/mL

Percent Error % error = abs value (actual – experimental) x100 actual Example: What is the percent error if an experiment created 5.0 grams of product when it was expected to create 5.5 grams? Answer: 9.1%

Download ppt "Significant Figures. 1.All nonzero digits are significant. Example: 145 (3 sig figs) 2.Zeroes between two significant figures are themselves significant."

Similar presentations