If you want to make 8.00 moles of AlF₃ how many moles of F₂ will you need, using the following balanced chemical equation? 2 Al + 3 F₂ → 2 AlF₃

You will need 12 moles of F2 if you want to make 8 moles of AlF3.

Explanation:

It takes 3 moles F2 to make 2 moles of AlF3 (this will be our mole ratio)

2 moles AlF3/3 moles F2 =8 moles AlF3/x moles AlF3.

x=12 moles AlF3

"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"