# When does a 0 count as a significant figure?

Sep 7, 2016

A zero is significant when it is between other significant figures and when it follows a significant figure after the decimal.

#### Explanation:

The following examples represent insignificant zeros.

0.537 cm$\Rightarrow$ 3 significant figures
0.00624 g$\Rightarrow$ 3 significant figures
150,000 m$\Rightarrow$ 2 significant figures

The following measurements have significant zeros.

806 km$\Rightarrow$ 1 significant zero; 3 significant figures
24.000 g$\Rightarrow$ 3 significant zeros; 5 significant figures
370.6080 m$\Rightarrow$ 3 significant zeros; 7 significant figures
0.073102 mol$\Rightarrow$ 1 significant zero; 5 significant figures