How many moles of CCI are there in 78.2 g of CCI.? 0.508 moles
12.028 moles
1.55 x 10-4moles
153.8 moles

0.508 mole

Explanation:

NOTE: Since no hydrogen is attached to the compound given in question above, it means the compound is CCl₄.

The number of mole present in 78.2 g of CCl₄ can be obtained as follow:

Mass of CCl₄ = 78.2 g

Molar mass of CCl₄ = 12 + (35.5×4)

= 12 + 142

= 154 g/mol

Mole of CCl₄ =?

Mole = mass / molar mass

Mole of CCl₄ = 78.2 / 154

Mole of CCl₄ = 0.508 mole

Therefore, 0.508 mole is present in 78.2 g of CCl₄

true

hope that

"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"