24.9 grams CaCO3=_________moles

Question

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Answer 1

Look up in your chemistry book the atomic weights of Ca, C, and O, in grams per mole.  Add them as follows to get the molecular weight of CaCO₃:

 

Ca + C + 3O

 

Divide the given mass of 24.9 grams by the molecular weight of CaCO₃.  Th result is the number of moles of CaCO₃.