Significant Figures Rules:
The number of significant figures can be determined by adding up each significant digit within the value using the following rules:
1.
All non-zero numbers are significant. a.
531 = 3 sig figs
2.
Zeros between non-zero numbers are significant. a.
Ex: 105 = 3 sig figs
3.
Zeros as placeholders, WITHOUT a decimal, are NOT significant. a.
Ex. 100 = 1 sig fig b.
Ex. 0.005 = 1 sig fig c.
Ex. 0.00503 = 3 sig figs (see rule 2)
4.
Zeros as place holders, WITH a decimal, ARE significant. a.
Ex. 100. = 3 sig figs
5.
A zero after the decimal point as the last value IS considered significant. a.
Ex. 0.050 = 2 sig figs (the last two digits of the number are significant)
6.
All numbers (including zeros) within the base number for scientific notation are significant. a.
Ex. 5.0 * 10 5 = 2 sig figs
7.
When converting numbers into scientific notation, the base should represent the number of significant figures in that number. a.
Ex. 1040 = 3 significant figures = 1.04*10 3
8.
Multiplication / Division: The final result should only have as many significant figures as the original value with the least number of significant figures in the calculation. a.
Ex. 25 * 355 = 8875 = 8900  The least number of sig figs is 2.