[avocado]

1) Mary added 10.0 g of calcium sulfate to 10.0 L of water. How many grams of the calcium sulfate did not dissolve?

i put together an ice table and solved for x (with ksp 7.1 x 10^-5 ) i got 6.9 x 10 ^-4 for x and subtracted that from 7.4 x 10 ^-3 (M of calcium sulfate?). now we have M dissolved which we convert to grams and subtract from total 1.0 gram. i got 0.09g not dissolved. i know its incorrect.


2) Paul prepares a solution to have an initial concentration of cadmium nitrate of 1.4x10^-4 M, sodium oxalate of 1.56 M and ammonia od 0.45 M. Does a precipitate form from this solution?

i know we need to find ksp to compare to qsp (1.4 x 10^-4M x 1.56 M x 0.45 M) but how do i set up the ice table?



3) When Joe makes a solution that 2.00 M sodium cyanide and 0.030 M copper (I) nitride, what is the equilibrium concentration of copper (I) ions?

not sure, but maybe need to use a completion table?