Chemistry

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One of the main components of hard water is CaCO3. When hard water evaporates, some of the CaCO3 is left behind as a white mineral deposit. If hard water solution is saturated with calcium carbonate, what volume of the solution has to evaporate to deposite 1.00x10^2 mg of CaCO3

• Chemistry - ,

CaCO3 ==> Ca^2+ + CO3^2-
Look up Ksp.
Ksp = (Ca^2+)(CO3^2-)
Set up an ICE chart and solve for solubility CaCO3. That value will be in moles/L. Multiply by molar mass to obtain grams/L. Then convert to volume necessary to hold 100 mg. Post your work if you get stuck.

• Chemistry - ,

I took the square root of (4.96x10^-9)= 7.04x10^-5 mol/L
then 100.09g/mol x 7.04 mol/L= 7.05x 10^-3 g/L
then .100 g x 1 L/ 7.05x10^-3= 7.05x10^-4 L, so that was my final answer, does this seem right?

• Chemistry - ,

Trista is almost correct. However she failed to realize that the problem called for 100 mg which is equal to 0.1 grams. This means that (7.05x10^-3)g/L / 0.1g = 0.0705/1L (Where the L is in the denominator).

So in order to finalize this problem all you have to do is take the inverse to get 1L/0.0705 = 14.2 L
The correct anwser.