Originally Posted by Roger C H
boiling water is 212°F (100°C) and ice water is 32°F (0°C) for testing.
(At considerable altitude, the boiling water is not accurate.)
These are approximate number for distilled water at sea level. The ice is ice water can be a lot colder than 32°F for one thing. These number are "transition" numbers where water changes from liquid to a solid or the other way around, and where water changes from liquid to a gas or the other way around. Do NOT confuse water vapor with steam.