Iodine is prepared both in the laboratory and commercially by adding Cl,(g) to an aqueous solution containing sodium iodide. 2 Nal(aq) + Cl2(g) → 1,(s) + 2 NaCl(aq)
How many grams of sodium iodide, Nal, must be used to produce 32.7 g of iodine, I2?
g Nal
mass:

"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"