Hi Ken,
Not much, aside from differences of a few percent in weight and freezing temperature.
Take a look at the Wikepedia article for more details.
LeeH
Those basic physical properties are pretty similar, but the differences do show up in important ways in chemical properties. Most importantly, the quantum zero-point motion of the D is less than of the H. As a result, the D is more tightly bound than the H. That chemical difference is a big deal for biology. As that Wikipedia article describes, you can't survive replacing H2O with D2O. /Mike W
(published on 12/29/2014)
