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What is the limiting reagent? Questions about chemical reactions

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2Al (s) + 2KOH (aq) + 4 H2SO4 (aq) + 22 H2O (l) --> 2KAl (SO4)2*12H2O (s) + 3H2 (g)

12.0 g of Al, 420 mL 2.0M KOH, 216 mL H2SO4 placed in 300 mL ice bath (water in excess)

1) What is the limiting reagent?
2) How much aluminum is necessary to produce 18g of alum?
3) By what factor must the mole amount of AL be reduced to produce 18 g alum?
4) What is the result of scaling the # moles of KOH used in the given procedure by this factor? What volume of 1.4M KOH contains this # moles?
5) What is the result of scaling the total # moles of H2SO4 used by this factor? What volume of 9.0M H2SO4 contains this # moles?
6) Scale the moles of sulfuric acid in a 54 mL portion of 10.0M H2SO4 by this factor. What volume of 9.0M H2SO4 contains this number of moles?
7) What is the result of scaling a 60 mL sample of distilled water by this factor?
8) What is the result of scaling down 300 mL 50/50 ethanol-water ice bath by this factor?

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1) To determine the limiting reactant find the moles of each reactant. Then divide these moles byt the coefficient of each term (for Al you would divide by 2, for KOH divide by ...

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This solution provides answers to various questions involving chemical reactions.

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Chemical Reactions and Stoichiometry Problems

Please assist with answering the following questions. I'd love to be able to see a step to step process for solving these, that way when I come across problems similar to this in the future and then, I don't get lost again.

1. 2Mn02 + 4KOH + O2 + CL2 ---> 2KMnO4 + 2KCL + 2H2O
For the reaction above, there is 100.0 g of each reactant available. Which reagent is the limiting reagent?

2. The reaction of 7.8 g of benzene (C6H6) with excess nitric acid resulted in 0.90 g of H2O. What is the percentage yield?
Molar mass (g/mol): C6H6=78, HNO3=63, C6H5NO2=123, H2O=18
C6H6 + HNO3 ----> C6H5NO2 + H2O

3. 6H+ + 5H2O + 2MnO4- ----> 5O2 + 2Mn2+ + 8H2O
According to the balanced equation above, how many moles of permanganate ion are required to react completely with 25.0 ml of .100 M hydrogen peroxide?

4. How many grams of water will be formed when 32.0 g of hydrogen is allowed to react with 16.0 g of oxygen according to the following reaction:
2H2 + O2 = 2H2O

5. What mass of Aluminum is produced when 0.5 mole of Al2S3 is completely reduced with excess H2?

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