Why Are Some Ice Cubes Cloudy While Others Are Clear?

The clarity of ice cubes is determined by the temperature of the water used to make them. Warmer water contains more impurities, which are released when the water is cooled and frozen. Ice cubes made from distilled or boiled water are usually clearer than those made from tap water. Even if you try freezing boiled water in your own freezer, it’s likely that the ice cubes formed will not be as clear as you might expect them to be. The reason is not related to the water being full of impurities but rather in how it’s cooled. To ensure that their ice cubes are as clear as possible, specialized ice makers freeze water in layers so that air bubbles do not form within the ice. Furthermore, they freeze water at a very slow pace, so large crystals of water are formed, and any bubbles that might have formed in the process have plenty of time to escape.