1 / 20

Stoichiometry

Stoichiometry. Chem 332 – O’Dette. Why care about stoichiometry?. Stoichiometry: allows us to predict the amounts of product produced or reactant needed in a reaction. Problem Types. Mole to Mole (one step) Mole to Mass (two steps) Mass to Moles (two steps) Mass to Mass (three steps).

sailor
Télécharger la présentation

Stoichiometry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Stoichiometry Chem 332 – O’Dette

  2. Why care about stoichiometry? • Stoichiometry: allows us to predict the amounts of product produced or reactant needed in a reaction

  3. Problem Types • Mole to Mole (one step) • Mole to Mass (two steps) • Mass to Moles (two steps) • Mass to Mass (three steps)

  4. Mole Ratio • A conversion factor that relates the amounts in moles of any two substances in a reaction • Use the coefficients in a balanced equation

  5. Mole to Mole • 2 Al2O3 4 Al + 3 O2 • Mole Ratios • 2 moles Al2O3 : 4 moles Al • 2 moles Al2O3 : 3 moles O2 • 4 moles Al : 3 moles O2

  6. Mole Ratio Conversion Factors • 2 moles Al2O3 4 moles Al • 2 moles Al2O3 3 moles O2 • 4 moles Al 3 moles O2 • Remember Reciprocals!!!

  7. Example #1 • If we have 12 moles of Al2O3, how many moles of Al and O2 are produced? • 12 moles Al2O3 x • 12 moles Al2O3 x 4 moles Al = 24 moles Al moles Al2O3 2 3 moles O2 18 moles O2 = 2 moles Al2O3

  8. Mole to Mass • Example #2 : How many grams of chlorine are required to react completely with 5.00 moles of sodium to produce sodium chloride? • 2 Na + Cl2 2 NaCl

  9. Example #2 (continued) 70.90 g Cl2 1 mole Cl2 • 5 moles Na x x 1 mole Cl2 2 mole Na Mole Ratio MM Use the mole ratio to convert to the substance asked for = 177 grams Cl2

  10. Example #3 • Calculate the mass of iodine required to react completely with 0.50 mole of aluminum to produce aluminum iodide. • 3 I2 + 2 Al 2AlI3

  11. Example #3 (continued) 253.8 g I2 3 mole I2 • .5 moles Al x x 1 mole I2 2 mole Al = 190 grams I2

  12. Mass to Mole • Example #4 : Calculate how many moles of zinc are required to make 10.0 g of zinc chloride. • Zn + Cl2 ZnCl2

  13. Example #4 (continued) 1 mole ZnCl2 1 moles Zn • 10 g ZnCl2 x x 1 mole ZnCl2 136.29 g ZnCl2 MM Mole Ratio = 0.0734 mole Zn

  14. Example #5 • Calculate the number of moles of ethane (C2H6) needed to produce 10.0 g of water in a combustion reaction. • 2 C2H6 + 7 O2 6 H2O + 4 CO2

  15. Example #5 (continued) 1 mole H2O 2 moles C2H6 • 10 g H2O x x 6 moles H2O 18.02 g H2O = 0.185 moles C2H6

  16. Mass to Mass • Mass Moles Moles Mass • These will be the steps every time!! Molar Mass Mole Ratio Molar Mass

  17. Example #6 • Tin(II) fluoride, SnF2, is used in some toothpastes it is made by the reaction of tin with hydrogen fluoride according to the following equation. • Sn + 2 HF SnF2 + H2

  18. Example #6 (continued) • How many grams of SnF2 are produced from the reaction of 30.00 g HF with Sn? • 30 g HF x xx 1 mole HF 1 mole SnF2 159.69 g SnF2 20.00 g HF 2 moles HF 1 mole SnF2 = 117.5 g SnF2

  19. Example #7 • When copper metal is added to silver nitrate in solution, silver metal and copper(II) nitrate are produced. What mass of silver is produced from 100 g of Cu? • Cu + 2 AgNO3 2 Ag + Cu(NO3)2

  20. Example #7 (continued) • 100 g Cu x xx 107.87 g Ag 1 mole Cu 2 moles Ag 1 mole Ag 1 mole Cu 63.55 g Cu = 300 g Ag

More Related