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HSC Stuff => HSC Science Stuff => HSC Subjects + Help => HSC Chemistry => Topic started by: aspiringfuturist on April 12, 2020, 09:27:24 pm

Title: Help with Ksp / solubility exam question
Post by: aspiringfuturist on April 12, 2020, 09:27:24 pm

Hi,

I'm struggling with this question - I feel like I've found out as much information as I can, using the information given and stoichiometry, but I'm really stuck now. The question is:

Some Ca(CO3)2 is dissolved in 100 mL of water. This solution is mixed with 300 mL of 0.010 M Na2SO4. A very faint precipitate of calcium sulfate is formed. If the Ksp value of calcium sulfate is 2.4 * 10^-5, how much calcium nitrate was dissolved to make the initial solution?

Any help would be greatly appreciated. Thanks.

Title: Re: Help with Ksp / solubility exam question
Post by: Kangaaroo on July 04, 2020, 08:32:20 pm

The question says calcium carbonate was dissolved, then says that a precipitate of calcium sulfate was formed, then asks how much calcium nitrate was initially dissolved. Are these typos on your part?