a hard H20 contains 0.0085% Ca by mass(form Ca+ ions).How much H2O(g) contains 1.2g of Ca?

3 answers

0.0085% means 0.0085g Ca^2+ ions/100 g solution.
g H2O = 100 x 1.2/0.0085 = ??
can i know why and where do you get the 100g solution? eventhough in the question it didt state anything about 100g.
.0085/100 (Flip it)

1.2g Ca x 100/.0085g Ca = 14,118 g soln

g H2O = 14118 - 1.2 = 14,116 g h2o