h We're off to see the wizard
The wonderful wizard of Oz
We hear he is a whiz of a Wiz
If ever a Wiz there was
If ever, oh ever, a Wiz there was
The wizard of Oz is one because
Because, because, because, because, because
Because of the wonderful things he does
We're off to see the wizard
The wonderful wizard of Oz!

Answer is in the file below

cutt.ly/nz6VGda

"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"