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M.7 (B)

Posted: Mon Apr 09, 2018 12:10 am
So this part of the problem asked us to find the mass of boron that can be produced when 125kg of boron oxide is heated with 125 kg of magnesium. The solution manual found the limiting reactant by comparing what amount of product each reactant would produce instead of comparing the relative amount of reactants like we learned in class. Is one way better to solve than the other or are we supposed to use one method in certain situations?

Re: M.7 (B)

Posted: Mon Apr 09, 2018 12:47 am
Hi!
Either method can be used to find the limiting reactant, which will be magnesium. However, since this problem is asking for the mass of boron that will be produced, the method used by the solution manual will find both the limiting reactant AND the mass of boron produced in one single calculation. This method is quicker and more efficient for this problem as the reactant which produces the smaller mass of boron will let you know that it is the limiting reactant as well.