SIGNIFICANT FIGURES
When you do calculations based on measurements that you take in the lab, your
answers can be only as precise as the measurements that you took. The way to
make sure all your calculations reflect the precision of your measurements is to
be aware of significant figures (or significant digits). The more significant
figures in the numbers you use, the more precise your answer will be. The
number of significant figures you use will be determined by the precision of
your measuring device.
The following are rules for recognizing and calculating with significant figures.
• Nonzero digits and zeros between nonzero digits are significant.
362 3 significant figures
4.609 4 significant figures
103.065 significant figures• Zeros to the left of the first nonzero digit in a number are not significant.
0.004 1 significant figure
0.08023 significant figures• Zeros at the end of a number to the right of the decimal point are
significant.
67.0005 significant figures
0.030 2 significant figures
2.0 2 significant figures• Zeros at the end of a number greater than 1 are not significant, unless
their significance is indicated by the presence of a decimal point.
2,600 2 significant figures
2,600.4 significant figures
50 1 significant figure- 2 significant figures
• The coefficients of a balanced equation and numbers obtained by