Some notes here from Honolulu community college, but the chart says it all.
Significant figures |
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OBJ: 1. Know how many numbers to round to for any given situation.
2. Be able to express extreme numbers in scientific notation.
Purpose: To state how PRECISE and ACCURATE your calculations are. We all know the calculator gives us a nearly infinite number of decimal places... but how many should we use and why?
Think of today's class activity to find out why. Remember your math is only as good as your measurements.
General rules for determining significant figures are on your formula charts!!
In the notes, ensure you KNOW THE DIFFERENCE between sig figs for MULTIPLYING and ADDING
2. Be able to express extreme numbers in scientific notation.
Purpose: To state how PRECISE and ACCURATE your calculations are. We all know the calculator gives us a nearly infinite number of decimal places... but how many should we use and why?
Think of today's class activity to find out why. Remember your math is only as good as your measurements.
General rules for determining significant figures are on your formula charts!!
In the notes, ensure you KNOW THE DIFFERENCE between sig figs for MULTIPLYING and ADDING
Scientific notation
Scientific notation is a method of expressing precision and accuracy with significant figures.
The number should always include exactly how many significant figures there are, and is very convenient for avoiding writing many zeroes.
Example: 1 mole of atoms (since they are so small we need a useful amount... more on this later) is 602000000000000000000000 atoms. The easy way is 6.02 x 10^23.
Example: 2 two atoms are 0.000000076 meters apart. The easy way is 7.6 x 10^ -8 meters.
The number should always include exactly how many significant figures there are, and is very convenient for avoiding writing many zeroes.
Example: 1 mole of atoms (since they are so small we need a useful amount... more on this later) is 602000000000000000000000 atoms. The easy way is 6.02 x 10^23.
Example: 2 two atoms are 0.000000076 meters apart. The easy way is 7.6 x 10^ -8 meters.