Stoichiometry for online

628
-1

Published on

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
628
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
16
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Stoichiometry for online

  1. 1. Stoichiometry
  2. 2. Stoichiometry is thestudy of quantitative relationships inchemical reactions.
  3. 3. The basic idea used insolving stoichiometric problems is the mole concept.
  4. 4. A short review
  5. 5. Molecular weight is the sum of the atomicweights of all the atoms in a molecule. A molecule is the smallest unit of a covalent compound.
  6. 6. What is a mole?
  7. 7. A mole (mol) is a SI baseunit used to measure the amount of material in a chemical sample.
  8. 8. 1 mole of H2O contains6.022 x 1023 H2O molecules (Avogadro’s number)
  9. 9. A coefficient in a balanced chemical equation indicates the number of moles of achemical compound involved in a chemical reaction. 2H2 + O2  2H2O
  10. 10. The coefficients give you themole ration of the compounds involved in the reaction. 2H2 + O2  2H2O The mole ratio of hydrogen to oxygen is 2:1 (for every oneoxygen put into the reaction, 2 moles of hydrogen are alsoneeded to put into the reaction)
  11. 11. The unit of moles provides a “bridge” to mathematically convertbetween several different aspects of chemical compounds.
  12. 12. Moles link an abstractchemical equation to a concrete unit ofmeasurement (grams, Liters, number of molecules)
  13. 13. For example:1 mole = 6.02 x 1023 molecules1 mole = molecular mass of a substance1 mole = 22.4 L of a substanceat STP (standard temperature and pressure)
  14. 14. For example:1 mol Cl = 6.02 x 1023 molecules Cl 1 mol H2O = 6.02 x 1023 molecules H 2O 1 mol Cl = 35.45g Cl 1 mol H2O = 18.01g H2O 1 mol Cl = 22.4L Cl @ STP 1 mol H2O = 22.4L H2O @ ATP
  15. 15. There are several types of calculations that can be used in Stoichiometry.
  16. 16. Mole – molecalculations
  17. 17. Involves 1conversion factor
  18. 18. The object of this type ofproblem is to calculate the moles of one substancewhen given the number of moles of different substance.
  19. 19. Example: Magnesiumhydroxide reacts with carbonicacid. How many moles of water will be produced from 3.5 moles of magnesium hydroxide? You are given the moles of one substance and asked to find the moles of another substance.
  20. 20. Example: How many molesof ammonia can be producedfrom 8.00 moles of hydrogen reacting with nitrogen?
  21. 21. Example:K2Cr2O7 + 6KI + 7H2SO4  Cr2(SO4)3 + 4K2SO4 + 3I2 + 7H2O Calculate the number of moles of potassium dichromate that will react with 2.0 moles of potassium iodide. Calculate the number of moles of iodine that will be produced from 2.0 moles of potassium iodide.
  22. 22. Mole – mass calculations
  23. 23. Involves 2conversion factors
  24. 24. The object of this type of problem is to calculate the moles of onesubstance when given the mass of different substance. Or vise versa
  25. 25. Example:What mass of hydrogen can be produced by reacting 6.0 moles of aluminum with hydrochloric acid? You are given the moles of one substance and asked to find the mass of another substance.
  26. 26. Example: How much carbon dioxide isproduced by the completecombustion of 0.0492 mol of propane, C3H8?
  27. 27. Example: How many moles of water will be produced from 14.6 g propane in thecombustion of propane?
  28. 28. Mass – Mass calculations
  29. 29. Involves 3conversion factors
  30. 30. The object of this type of problem is to calculate the mass of onesubstance when given the mass of different substance.
  31. 31. Example:How much carbon dioxide is produced by the complete combustion of 100.0 g of propane, C3H8? You are given the moles of one substance and asked to find the mass of another substance.
  32. 32. Example: Magnesium chloride reacts withsulfuric acid. How muchsulfuric acid is needed to produce 26.3 g of magnesium sulfate?
  33. 33. Calculationsinvolving Liters and number of molecules
  34. 34. Example: How many molesof ammonia can be producedfrom 1.03 Liters of hydrogen reacting with nitrogen at STP?
  35. 35. Example: How many carbon dioxide molecules are produced by the completecombustion of 32.00 grams of propane, C3H8?

×