Mass of one mole (Avogadro Number) of neutrons ~ 1 g
Mass of the one neutrons =(1 /ย ๐ด๐ฃ๐๐๐๐๐๐ ๐๐ข๐๐๐๐ (๐๐ด)) g
Mass of 8 molecule of water = ๐๐๐๐๐ ๐๐๐ ๐ / ๐๐ด
= 18 / ๐๐ดย ย g
There are 8 neutrons of water = 18 / ๐๐ด
Mass of one molecule of water = ๐๐๐๐๐ ๐๐๐ ๐ / ๐๐ด
= 18 / ๐๐ดย ย g
Fraction off mass of the water due to neutrons ~ 8 / 18
.