• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
17 stoichiometry
 

17 stoichiometry

on

  • 576 views

 

Statistics

Views

Total Views
576
Views on SlideShare
576
Embed Views
0

Actions

Likes
0
Downloads
0
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment
  • http://www.youtube.com/watch?v=wyrFWbGiGOc

17 stoichiometry 17 stoichiometry Presentation Transcript

  • STOICHIOMETRY
  • STOICHIOMETRY 1 molecule of O2 2H2 + O2  2H2O2 molecules of H2 2 molecules of H2O Now that you know the mole… 1 mole of O2 2H2 + O2  2H2O 2 moles of H2 2 moles of H2O
  • STOICHIOMETRY 1 mole of O2 2H2 + O2  2H2O 2 moles of H2 2 moles of H2O Think of a reaction as a ratio… 2 moles H2 : 1 mole O2 : 2 moles H2O This is called a mole ratioMultiply by 2 = 4 moles H2 : 2 mole O2 : 4 moles H2O
  • STOICHIOMETRY 2 moles H2 : 1 mole O2 : 2 moles H2O How many molecules of water are formed when 3.5 moles of O2 react with H2?= [2 moles H2 : 1 mole O2 : 2 moles H2O] x 3.5= 7 moles H2 : 3.5 moles O2 : 7 moles H2O 7 moles of waterN = n x NA = 7 mol water x 6.02x1023 molecules/mol = 4.21x1024 molecules of water Therefore 4.21x1024 molecules of water are formed.
  • STOICHIOMETRY C2H6 + O2  CO2 + H2OA) How many moles of O2 are required toreact with 13.9mol of C2H6 (ethane)?B)What volume of H2O would be producedby 1.40 mol of O2 and sufficient ethane
  • STOICHIOMETRY C2H6 + O2  CO2 + H2OShould always balance the equation first 2C2H6 + 7O2  4CO2 + 6H2O
  • STOICHIOMETRY 2C2H6 + 7O2  4CO2 + 6H2OA) How many moles of O2 are required to react with 13.9mol of C2H6 (ethane)?iven: mole ratio of C2H6:O2 = 2:7 moles of C2H6 = 13.9mol 2 mol C2H6 = 13.9 mol C2H6 7 mol O2 x 0.2857 = 13.9 x x = 13.9 0.2857 = 48.6 mol of O2 Therefore 48.6 mol of O2 are required
  • STOICHIOMETRY 2C2H6 + 7O2  4CO2 + 6H2OWhat volume of H2O would be produced by 1.40 mol of O2 and sufficient ethaneiven: mole ratio of O2:H2O = 7:6 moles of O2 = 1.40mol 6 mol H2O = x 7 mol O2 1.40 mol O2 0.8571 = x 1.40 x = 0.8571 x 1.40 = 1.20 mol of H2O But the question asked for volume!!!
  • STOICHIOMETRY 2C2H6 + 7O2  4CO2 + 6H2OWhat volume of H2O would be produced by 1.40 mol of O2 and sufficient ethane x = 1.20 mol of H2O Given: n = 1.20 mol MH2O = 18.016 g/mol m=? m = nxM = 1.20 mol x 18.016 g/mol = 21.6 g 1 gram of water = 1mL at room temperature Therefore the volume of water produced is 21.6mL
  • STOICHIOMETRYGeneral rules for solving problems…STEP 1: Write a balanced chemical equationSTEP 2: If you’re given m or N of a substance, convert it to the number of molesSTEP 3: Calculate the number of moles of the required substance based on the number of moles of the given substance (using the appropriate mole ratio)STEP 4: Convert the number of moles of the required substance to mass or number of particles, as directed by the question
  • STOICHIOMETRYPassing chlorine gas through moltensulfur produces liquid disulfur dichloride.How many molecules of chlorine react toproduce 50.0g of disulfur dichloride?
  • STOICHIOMETRYPassing chlorine gas through molten sulfur produces liquiddisulfur dichloride. How many molecules of chlorine react toproduce 50.0g of disulfur dichloride?STEP 1: Write the balanced equation2S + Cl2  S2Cl2STEP 2: Convert the given mass of disulfur dichlorideto the number of molesMS2Cl2 = 135.04g/moln = m/M = 50.0g/135.04g/mol = 0.37026mol
  • STOICHIOMETRYPassing chlorine gas through molten sulfur produces liquiddisulfur dichloride. How many molecules of chlorine react toproduce 50.0g of disulfur dichloride?STEP 3: Calculate the number of moles of the requiredsubstance using your mole ratio2S + Cl2  S2Cl2Given: mole ratio of S2Cl2:Cl2 = 1:1 1 mol S2Cl2 = 0.37026 mol S2Cl2 1 mol Cl2 x x = 0.37026 mol Cl2
  • STOICHIOMETRY Passing chlorine gas through molten sulfur produces liquid disulfur dichloride. How many molecules of chlorine react to produce 50.0g of disulfur dichloride?STEP 4: Convert the number of moles of chlorine gas to thenumber of particlesx = 0.37026 mol Cl2N = n x NA = 0.37026mol x 6.02x1023 molecules/mol = 2.23 x 1023 moleculesTherefore the number of molecules of chlorine is 2.23 x 10 23
  • STOICHIOMETRYTHE LIMITING REACTANT…
  • STOICHIOMETRY THE LIMITING REACTANT… 2C2H6 + 7O2  4CO2 + 6H2ONormally, we assume that all reactants areconsumed in a reaction…Reactants are said to be in stoichiometicamounts when all reactants are consumed inthe ratios predicted
  • STOICHIOMETRY THE LIMITING REACTANT… 2C2H6 + 7O2  4CO2 + 6H2OBut there are often reactants that remain“unreacted”… O2 O2 O2 O2 O2 GAS GAS
  • STOICHIOMETRY THE LIMITING REACTANT…Lithium nitride reacts with water toform ammonia and lithium hydroxide.If 4.87g of lithium nitride reacts with5.80g of water, find the limitingreactant.
  • STOICHIOMETRY THE LIMITING REACTANT… Lithium nitride reacts with water to form ammonia and lithium hydroxide. If 4.87g of lithium nitride reacts with 5.80g of water, find the limiting reactant.STEP 1: Write a balanced chemical equation Li3N + 3H2O  NH3 + 3LiOH
  • STOICHIOMETRY THE LIMITING REACTANT…Lithium nitride reacts with water to form ammonia and lithium hydroxide.If 4.87g of lithium nitride reacts with 5.80g of water, find the limitingreactant. STEP 1: Write a balanced chemical equation Li3N + 3H2O  NH3 + 3LiOH STEP 2: Convert the given masses to the number of moles nLi3N = m/M = 4.87g/34.8g/mol = 0.140mol nH2O = m/M = 5.80g/18.0g/mol = 0.322mol
  • STOICHIOMETRY THE LIMITING REACTANT…Lithium nitride reacts with water to form ammonia and lithium hydroxide.If 4.87g of lithium nitride reacts with 5.80g of water, find the limitingreactant. Li3N + 3H2O  NH3 + 3LiOHnLi3N = 0.140molnH2O = 0.322mol STEP 3: Calculate the number of moles of NH3 produced by both amounts of reactants 1 mol Li3N = 0.140 mol Li3N 1 mol NH3 x x = 0.140 mol NH3
  • STOICHIOMETRY THE LIMITING REACTANT…Lithium nitride reacts with water to form ammonia and lithium hydroxide.If 4.87g of lithium nitride reacts with 5.80g of water, find the limitingreactant. Li3N + 3H2O  NH3 + 3LiOHnLi3N = 0.140molnH2O = 0.322mol STEP 3: Calculate the number of moles of NH3 produced by both amounts of reactants 3 mol H2O = 0.322 mol H2O 1 mol NH3 x x = 0.107 mol NH3 5.80g water makes less ammonia than 4.87g lithium nitride
  • STOICHIOMETRY THE LIMITING REACTANT…Lithium nitride reacts with water to form ammonia and lithium hydroxide.If 4.87g of lithium nitride reacts with 5.80g of water, find the limitingreactant. Li3N + 3H2O  NH3 + 3LiOH Therefore water is the limiting reactant
  • STOICHIOMETRY THE LIMITING REACTANT… P4 + O2  P4O10 A 1.00g piece of phosphorus is burned in aflask filled with 2.60x1023 molecules of oxygen gas. What mass of tetraphosphorus decaoxide is produced?
  • STOICHIOMETRY THE LIMITING REACTANT…A 1.00g piece of phosphorus is burned in a flask filled with 2.60x1023 molecules ofoxygen gas. What mass of tetraphosphorus decaoxide is produced?STEP 1: P4 + 5O2  P4O10STEP 2: nP = 1.00g P4 no = 2.60x1023 molecules 123.9g/mol P4 6.02x1023molecules/mol = 8.07x10-3 mol = 0.432 mol O2 LIMITING REACTANTSTEP 3: Amount of P4O10 produced by P4 = 8.07x10-3 mol Amount of P4O10 produced by O2 = 0.432 ÷ 5 = 8.64 x 10-2 mol
  • STOICHIOMETRY THE LIMITING REACTANT…A 1.00g piece of phosphorus is burned in a flask filled with 2.60x1023 molecules ofoxygen gas. What mass of tetraphosphorus decaoxide is produced?Amount of P4O10 produced by P4 = 8.07x10-3 molm= n x M = 0.00807mol x 284g/mol P4O10 = 2.29g P4O10 Therefore 2.29g of P4O10 is produced.
  • STOICHIOMETRY THE LIMITING REACTANT…empty case battery circuitry iphone 4 1 + 1 + 1  1
  • STOICHIOMETRY THE LIMITING REACTANT…empty case battery circuitry iphone 4What if you were given… Limiting ingredient 3 + 6 + 1  1 ? How many iphones can you make?
  • STOICHIOMETRY THE LIMITING REACTANT…empty case battery circuitry iphone 4What if you were given… 101 + 64 + 97  64 ? Limiting ingredient How many iphones can you make?