In this instance, when determining number of significant figures, we should use the Kelvin values instead of Celsius, since it would give us the value of absolute temperature. When we convert values we see that -196°C is actually 77 K, and it has two significant figures, while -25°C is 298 K, and it has three significant figures.
Work Step by Step
Kelvin scale is absolute, while Celsius is relative to the boiling and freezing points of water. To convert from Celsius scale to Kelvin, we use the following equation: K=°C+273