When calculating the percentage of water of crystallization (in an alum) by mass, do we take the ratio of.....?
.....(water mass/alum mass)x100% or the ratio:
(water mass/anhydrous salt mass)x100%?
.....(water mass/alum mass)x100% or the ratio:
(water mass/anhydrous salt mass)x100%?
Dr W
Favorite Answer
% water = mass water / mass total x 100%
so the answer is (water mass / alum mass) x 100%
darkskies4evr
Use:
(water mass/alum mass)x100%
You want the percentage mass of water in the alum, not the anhydrous salt.
mackley
mw of CaSO4 is 136.14 g/mol (anhydrous) a hundred g CaSO4 XH2O have 20.9 g of water(mw is eighteen) or a million.sixteen mol; and seventy 9.a million g CaSO4 or 0.581 mol, so the mol relation is approx a million:2 meaning x=2 CaSO4 *2H2O