My son did this experiment and showed me these two blocks of ice made from the same water… and asked me how they were different… One was more transparent, and the other was more whitish and transclucent.
I realized I was unclear about the answer, but before my gray cells could warm up… he told me the answer.
If you have time to chill, you can think it over….
As the ice blocks are made from the same water – there’s no difference in purity or freezing.
Scroll down for the answer……
Virtually all natural water you deal with is oxygenated to some extent. It’s why fish can breathe in it.
As the water freezes, it wants to form a regular crystalline structure (ice). That means oxygen and other dissolved gasses are pushed away from the crystallization front into the remaining liquid. So the last parts of the ice cube to crystallize end up with most of the gasses. In home made ice cubes, you’ll note that the parts of the ice cube that were at the bottom of the tray are more whitish. That’s because those were the last parts to freeze. The ice cubes in your tray froze from the top downward, which pushed the air downward until it was trapped at the bottom and had nowhere else to go.
If you boil the water first, you remove the oxygen from it. Next, cool it and then pour it into your ice cube trays to freeze. It should be much more clear.~ Based on: Forbes: center of an ice cube white?
On the lighter side, in the movie Finding Nemo, there’s a fish in the tank … which is obsessed with “my bubbles“