Why is it that ice is transparent/translucent and snow is white?

Question

Why is it that ice is transparent/translucent and snow is white?

Answer 1

ice contains minimum amount of trapped air .. but snow contains lot of trapped air bubbles and impurities..and also snow is very powdery substance..the factors light to scatter and the snow appears white ..

Answer 2

It has to do with the size of the ice particles. It is the reason that snow is white, but a solid chunk of ice is transparent. This actually works the same for any materials -- for instance, glass is transparent, but if you grind it into a fine powder, it will look white.

The reason is that every time light reaches the edge of new material -- goes from passing through air to passing through another substance and again back to air -- some light is reflected off the surface.

When you look at a big block of ice, the light enters the ice once, and exits it once. When you look at snow, or crushed ice, there are thousands of little ice crystals and the light passes through many many of these crystals, going from air to ice to air to ice to air to ice, etc. Each time it does this, more light is scattered, and if it does it enough, all the light is scattered and no light makes it through -- so that the object looks completely white. The finer the particles, the more it does this. Crushed ice has bigger particles than snow does, so it look a bit white, but you can still see through it. Same effect when you have frost on your windows -- it looks white because the frost is made up of tiny particles of ice that scatter the light.

NOTE: Often, even a large chunk of ice, such as an ice cube or a glacier or ice on a lake will also appear white. While it is not composed of many particles, it still looks white. Why? This is because there are many small air bubbles trapped inside the ice, and it is these bubbles that cause it to look white. Each time the light passes from ice to air bubble and back to ice, light is reflected and scattered, just as described above.