What is the  ▲ of a snowflake?  

A diameter of a snowflake is≥2mm.

One cubic meter of snow includes 6 to 8 billion snowflakes.

As for the snow in the northern and southern part of China, which is heavier?

The same amount of snowfall may cover an area differently in northern and southern China because the snow in the northern part of China is loosewhile the snow in the southern part is tight.

Is snow always white?

Snow is not actually white but clear. It looks white because of the way the light reflects off of the ice crystals. However, it is made of water. Large amounts of frozen water really are pale blue, so a lot of snow, will show this blue color. But white and blue are not the only colors of snow or ice. Algaecan grow on snow, making it appear more red