Proportions with moles

Question

I have a proportion that for every 1 mol of Aluminum, I get 1.5 mol Copper. How much aluminum will I need if I have 127,226,463.1 grams of copper? 

Answer 1

Good Evening Ryan

 

You will have to set up a stoichiometry conversion where the given grams of copper is converted to grams of Aluminum using the mole ratio stated in your question.  The stoichiometry can be summarized as:

 

g copper --> mole copper --> mole aluminum --> g aluminum

 

 

Step 1 - Convert grams of copper to moles of copper using its molar mass, which is 63.55 g/mol

 

127,226,463.1 g Cu x (1 mol Cu / 63.55 g Cu) =  2,001,989.978 mol Cu  (rounded to 10 significant figures according to the mass of copper)

 

 

Step 2 - Use the mole ratio to convert moles of copper to moles of aluminum

 

2,001,989.978 mol Cu  x  (1 mol Al / 1.5 mol Cu)  =  1,334,659.985 mol Al

 

 

Step 3 - Convert moles of aluminum to grams of aluminum using its molar mass, which is 26.98 g/mol

 

1,334,659.985 mol Al  x  (26.98 g Al / 1 mol Al)  =  36,009,126.40 g Aluminum

 

 

Hope the above resolved your query!