RICE tables are a common tool of chemists (college professors use then a lot!) to organize the...

USING R.I.C.E. TABLES AND STOICHIOMETRY WITH LIMITING REACTANTS

RICE tables are a common tool of chemists (college professors use then a lot!) to organize the information for stoichiometry with a reaction and set up mathematical equations when necessary to solve for unknowns.

R = reaction (balanced)I = initial conditions (before the reaction)C = change (remove reactants, form products)E = end conditions (after the reaction)

Example 1: 10. grams of ethene is combusted. What volume of carbon dioxide will be formed?


BEWARE: Moles goes into a RICE table and moles will come out. To find volume will require a final step.


R =


R = C2H4 + 3O2 → 2CO2 + 2H2O


R = C2H4 + 3O2 → 2CO2 + 2H2O

I =


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

C =


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

C = -1x -3x +2x +2x


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

C = -1x -3x +2x +2xall the ethene will be burned, so x = 0.63 mol


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

C = -1x -3x +2x +2x-0.625 mol -1.875 mol +1.25 mol +1.25 mol


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0


E =


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0


E = 0 ?-1.875 mol 1.25 mol 1.25 mol


How many moles of CO2 was formed?


How many moles of CO2 was formed? 1.3 mol


How many moles of CO2 was formed? 1.3 molWhat volume of CO2 was formed?



1.25 mol x 22.4 L/mol = 28 L



1.25 mol x 22.4 L/mol = 28 L

What other information do we already know?



1.25 mol x 22.4 L/mol = 28 L

What other information do we already know?• Moles of O2 consumed• Moles of H2O produced

Example 2: 10. grams of ethene is combusted with 50. grams of O2. What volume of carbon dioxide can be formed?


R = C2H4 + 3O2 → 2CO2 + 2H2O


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g 50. g0.625 mol 1.56 mol


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g 50. g0.625 mol 1.56 mol

C = -1x -3x +2x +2xWHICH X TO USE? SMALLEST X!


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g 50. g0.625 mol 1.56 mol

C = -1x -3x +2x +2xWHICH X TO USE? SMALLEST X!

If 0.625 = 1 x, then x = 0.625If 1.56 = 3 x, then x = 0.521 ← SMALLEST


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g 50. g0.625 mol 1.56 mol

C = -1x -3x +2x +2x-0.521 mol -1.56 mol +1.04 mol 1.04 mol


R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g 50. g0.625 mol 1.56 mol

C = -1x -3x +2x +2x-0.521 mol -1.56 mol +1.04 mol 1.04 mol

E = 0.625 mol – 0.521 mol 1.56 mol – 1.56 mol 1.04 mol 1.04 mol

0.104 mol 0 1.04 mol 1.04 mol


What volume of CO2 is actually produced?1.04 mols x 22.4 L/mol = 23 L


What volume of CO2 is actually produced?1.04 mols x 22.4 L/mol = 23 L

What else do we know?• Moles of ethene left over• Moles of water actually produced

Why use a RICE table for limiting reactant problems?

How many RR tracks would it have taken?


How many RR tracks would it have taken?2 to figure out which one is limiting


How many RR tracks would it have taken?2 to figure out which one is limiting1 more to find amount of excess


How many RR tracks would it have taken?2 to figure out which one is limiting1 more to find amount of excess1 more for each of the additional products


How many RR tracks would it have taken?2 to figure out which one is limiting1 more to find amount of excess1 more for each of the additional products

It is your choice. We did 1 RICE table vs 4 RR Tracks.RICE tables will be necessary later. For now, it is optional.

RICE tables are a common tool of chemists (college professors use then a lot!) to organize the...

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