Question

Honors Chemistry Worksheet on Limiting Reactants Show all work in solving the following problems. Express any equations used. Utilize dimensional analysis format wherever possible. Include All units, labels, significant figures, and work. 3 O2(8) Al+ 2 Al2O3(6); 1. Using the reaction: Identify the limiting reactant/reagent for each of the following: a) 0.225 mol Al reacts with 0.415 mol O2 b) 77.9 g Al reacts with 111.9 g O2 c) 58.7 g Al reacts with 98.2 g O2

Answer 1

   4Al(s) + 3O2(g) ----------------> 2Al2O3(s)

3 moles of O2 react with 4 moles of Al

0.415 moles of O2 react with = 4*0.415/3   = 0.553 moles of Al is required.

Al is limiting reactant

b.

no of moles of Al    = W/G.A.Wt

                               = 77.9/27   = 2.885 moles

no of moles of O2   = 111.9/32    3.5 moles of O2

4Al(s) + 3O2(g) ----------------> 2Al2O3(s)

3 moles of O2 react with 4 moles of Al

3.5 moles of O2 react with = 4*3.5/3   = 4.67 moles of Al is required

Al is limiting reactant

c.

no of moles of Al    = W/G.A.Wt

                               = 58.7/27   = 2.174 moles

no of moles of O2   = 98.2/32 = 3.06875 moles of O2

4Al(s) + 3O2(g) ----------------> 2Al2O3(s)

3 moles of O2 react with 4 moles of Al

2.174 moles of O2 react with = 4*2.174/3 = 2.9 moles of Al is required

Al is limiting reactant