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

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Transcript of 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?

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.

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

R =

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

I =

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

C =

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

R = C2H4 + 3O2 → 2CO2 + 2H2O

I = 10. g0.625 mol ? 0 0

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

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

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

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

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

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

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

E =

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

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

E = 0 ?-1.875 mol 1.25 mol 1.25 mol

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

How many moles of CO2 was formed?

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

How many moles of CO2 was formed? 1.3 mol

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

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

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

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

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

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

What other information do we already know?

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

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

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?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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?

Why use a RICE table for limiting reactant problems?

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

Why use a RICE table for limiting reactant problems?

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

Why use a RICE table for limiting reactant problems?

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

Why use a RICE table for limiting reactant problems?

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.