Suppose we have a compound that is 4.330 % li, 22.10 % cl, 39.89 % o, and 33.69 % h2o. what is the compounds formula?

The  formula   of compound is   LiClO4.3H2O

      calculation

        that is  moles for Li,Cl,O and that of H2O

       For Li = 4.330/ 6.94 g/mol=  0.624 moles

             Cl=22.10/35.5=0.623  moles

           39.89/16 g/mol =2.493  moles

           H20=  33.69/18 g/mol=  1.872  moles

        that  is  for  Li= 0.624/0.623=  1

                             Cl= 0.623/0.623=1

                             O = 2.493/0.623 =4

                          H2O= 1.872/0.623=3

"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"