How many grams of KIO3 are needed to prepare 100.0 mL of 0.0030 M KIO3

Standardization of the Sodium Thiosulfate Solution Make up a standard solution of potassium iodate by accurately “weighing by difference” about 0.1 g of KIO3 and placing it in your 100 mL volumetric flask. Fill the flask to mark with distilled water. 

The solubility-product constant for Ce(Io3)3 is 3.2 x 10^-10. What is the Ce^3+ concentration in a solution prepared by mixing 50.0 ml of 0.0500 M Ce^3+ with 50.00 ml of a. water b. 0.050 M Io3- c. 0.150 M Io3- d. 0.300 M Io3-

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"