Red is the conventional color for how to depict oxygen. Blue is the conventional color for nitrogen.
The convention is called "CPK coloring" after Robert Corey, Linus Pauling, and Walter Koltun. See http://en.wikipedia.org/wiki/CPK_coloring .
The convention is called "CPK coloring" after Robert Corey, Linus Pauling, and Walter Koltun. See http://en.wikipedia.org/wiki/CPK_coloring .
"BIG ICE: Liquid water (left) is composed of hydrogen (white) and oxygen (red) atoms arranged in a nearly tetrahedral structure. Common ice, or Ice Ih (right), shows a three-dimensional network that is less dense, explaining why ice floats on water."