snow

The white that you see is actually a reflection of the sun's rays off of the ice crystals and pockets of air. There is a really good/better explanation at this URL, (about halfway down the page): http://www.discovery.com/area/skinnyon/skinnyon971003/skinnyon.html Gee, we ALL learned something new today!

when the butter melts its white goes and turns colourless in the same way snow melts

it's not actually white but it's the refelction which you can see on the snow.

If you catch one snowflake on your finger you'll see that it isn't really white. Like someone else said, it's just light reflecting off the crystals.

I dont know, good question, where does the yellow go when the snow melts and a dog has peed on it.