= Ice =

 . about 0.9 g/cm³

 . 0.9162 @ 0 °C
 . 0.9216 @ -50 °C
 . 0.9257 @ -100 °C
 . 0.93 @ -220 °C est

18 g/mole → 3.1e28/m³, 3.1e9/m 

Stadyshell  0.3 μm → 1000 ice molecules thick