When we look into the ice cubes, there is a white colored part in the middle(inside at the center). I google searched and most of them say it's the colour of the gases trapped inside when it froze. But there are no white coloured gases inside. is there? lets take oxygen, its a colourless gas. CO2 , colourless........ etc. So why is ice white?? is it due to the impurities inside it?