Presentation on theme: "Mole Review 1.) Calculate the number of moles in 60.4L of O2. 2.) How many moles are there in 63.2g of Cl2? 1 mol O2 60.4L O2 = 2.7 mol O2 22.4L O2 1mol."— Presentation transcript:
1 Mole Review1.) Calculate the number of moles in 60.4L of O2. 2.) How many moles are there in 63.2g of Cl2?1 mol O260.4L O2= 2.7 mol O222.4L O21mol Cl263.2g Cl2= 0.903mol Cl270g Cl2
2 Math In Chemistry Stoichiometry Unit 08Math In ChemistryStoichiometry
3 Scheduled to make 640 tricycles. How many wheels should they order? Proportional RelationshipsTiny Tyke Tricycle CompanyF + S + 3W + H + 2P → FSW3HP2Scheduled to make 640 tricycles. How many wheels should they order?
4 Proportional Relationships 2 1/4 c. flour1 tsp. baking soda1 tsp. salt1 c. butter3/4 c. sugar3/4 c. brown sugar1 tsp vanilla extract2 eggs2 c. chocolate chipsMakes 5 dozen cookies.I have 5 eggs. How many cookies can I make?Ratio of eggs to cookies5 eggs5 doz.2 eggs= 12.5 dozen cookies
5 Proportional Relationships Stoichiometrymass relationships between substances in a chemical reactionfor example: you can determine the amount of a compound required to make another compoundbased on the mole ratioMole Ratioindicated by coefficients in a balanced equation2 Mg + O2 2 MgO2 Moles of magnesium react with 1 mole of oxygen to form 2 moles of magnesium oxide.
6 2 Mg + O2 2 MgOWhat would be the mole ratio of magnesium to magnesium oxide? 2 : 2 Conversion factor = 2 mol Mg 2 mol MgO What would be the mole ratio of oxygen to magnesium? 1 : 2 Conversion factor = 1 mol O2 (Mole Ratio) 2 mol Mg
7 Practice5 F2 + 2NH3 N2F4 + 6HF1. What is the mole ratio of NH3 to F2?Write the mole ratio as a conversion factor.2. What is the mole ratio of HF to N2F4?2:52mol NH35mol F26:16mol HF1mol N2F4
8 Stoichiometry Steps 1. Identify known & unknown. 2. Convert known to mole. (if necessary)3. Use Mole Ratio.4. Convert moles to unknown unit. (if necessary)Mole ratio- get from equationUnits of unknownknownMol of unknownMol of knownMol of unknown
9 Mass-Mass Stoichiometry Mass of reactants equals the productsLaw of Conservation of MassONLY mass and atoms are conserved in every chemical reactionKnown g1 mol KnownMolar massKnownmol unknownmol knownMol ratio-get from equationMolar mass unknown1 mol unknown
10 Mass-Mass Stoichiometry #1The reaction of fluorine with ammonia produces dinitrogen tetrafluoride and hydrogen fluoride.5F2 + 2 NH3 → N2F4 + 6HFHow many grams of NH3 are required to produce 7.38g HF?
11 Mass-Mass Stoichiometry #25F2 + 2 NH3 → N2F4 + 6HFHow many grams of N2F4 can be produced from 265g F2?
12 Mass-Mass Stoichiometry #32C2H2 + 5O2 → 4CO2 + 2H2OHow many grams of oxygen are required to burn 52.0g C2H2?
13 C. Stoichiometry Problems How many grams of silver will be formed from 12.0 g copper?Cu + 2AgNO3 2Ag + Cu(NO3)212.0 g? g12.0g Cu1 molCu63.55g Cu2 molAg1 molCu107.87g Ag1 molAg= 40.7 gAg
14 C. Stoichiometry Problems Calculate the number of grams of NH3 produced by the reaction of 5.40 g of hydrogen with an excess of nitrogen.N2 + 3H2 → 2NH3
15 C. Stoichiometry Problems Acetylen gas (C2H2) is produced by adding water to calcium carbide (CaC2).CaC2 + 2H2O C2H2 + Ca(OH)2How many grams of acetylene are produced by adding water to 5.00 g CaC2?Using the same equation, determine how many moles of CaC2 are needed to react completely with 49.0 g H2O.
16 Mole-Mole Examples __S + __O2 → __SO3 Write the equation. #1__S + __O2 → __SO3Write the equation.Balance the equation.How many moles of SO3 are produced when there are 4.5 moles of S?Known =Unknown =
17 Mole-Mole Examples 2C3H7OH + 9O2 → 6CO2 + 8H2O Write the equation. #2Isopropyl alcohol (C3H7OH) burns in the air to this equation:2C3H7OH + 9O2 → 6CO2 + 8H2OWrite the equation.Calculate the moles of oxygen needed to react with 3.40 moles of isopropyl alcohol.
18 Mole-Mole Examples 2C3H7OH + 9O2 → 6CO2 + 8H2O #32C3H7OH + 9O2 → 6CO2 + 8H2OFind the moles of water when 6.20 mol O2 reacts with C3H7OH.
19 C. Stoichiometry Problems How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?2KClO3 2KCl + 3O2? mol9 mol9 mol O22 mol KClO33 mol O2= 6 molKClO3
20 Volume-Volume Stoichiometry Formula to use:Known (L) 1 mol known mol unknown L unknownL known mol known mol unknown
21 Volume Example C3H8 + 5O2 → 3CO2 + 4H2O #4C3H8 + 5O2 → 3CO2 + 4H2OIf 20 liters of oxygen are consumed in the above reaction, how many liters of carbon dioxide are produced?
22 C. Mixed Stoichiometry Problems How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?2KClO3 2KCl + 3O2? mol9 mol9 mol O22 mol KClO33 mol O2= 6 molKClO3
23 C. Mixed Stoichiometry Problems How many grams of KClO3 are required to produce 9.00 L of O2 at STP?2KClO3 2KCl + 3O2? g9.00 L9.00 LO21 molO222.4 L2 molKClO33 molO2122.55g KClO31 molKClO3= 32.8 gKClO3
24 Limiting Reactants/Reagents Available Ingredients4 slices of bread1 jar of peanut butter1/2 jar of jellyLimiting Reactant/ReagentsbreadExcess Reactants/Reagentspeanut butter and jelly
25 Limiting Reactants/Reagents Limiting Reactant/Reagentused up in a reactiondetermines the amount of productExcess Reactant/Reagentadded to ensure that the other reactant is completely used upcheaper & easier to recycle
26 Limiting Reagents 1. Write a balanced equation. 2. For each reactant, calculate the amount of product formed.3. Smaller answer indicates:limiting reactantamount of product
27 Limiting Reagents Zn + 2HCl ZnCl2 + H2 79.1 g of zinc react with 0.90 L of HCl. Identify the limiting and excess reactants. How many liters of hydrogen are formed at STP?Zn HCl ZnCl H279.1 g0.90 L? L
28 Limiting Reagents Zn + 2HCl ZnCl2 + H2 79.1 g 0.90 L ? L 79.1 g Zn 1 molZn65g Zn1 molH2Zn22.4 LH21 mol= 27.3 LH2
29 Limiting Reagents Zn + 2HCl ZnCl2 + H2 79.1 g 0.90 L ? L 0.90 L HCl 1 molHCl22.4L HCl1 molH22 molHCL22.4 LH21 mol= 0.45 LH2
30 Limiting Reagents Zn: 27.3 L H2 HCl: 0.45 L H2 Limiting reagent: HCl Excess reagent: Zn
31 Percent YieldPercent yield- the ratio of the actual yield to the theoretical yieldActual yield- the amount of product formed when a reaction is carried out in the laboratoryTheoretical yield- the calculated amount of product formed during a reaction
32 Percent Yieldmeasured in labcalculated on paper32
33 Percent Yield K2CO3 + 2HCl 2KCl + H2O + CO2 When 45.8 g of K2CO3 react with excess HCl, 46.3 g of KCl are formed. Calculate the theoretical and % yields of KCl.K2CO3 + 2HCl 2KCl + H2O + CO245.8 g? gactual: 46.3 g
34 Formulas to Use Mole - Mole Known mol of unknown mol of known Mol Ratio – from equationMass - Massmol of unknownKnown g1 mol knownmolar mass unknownmol of known1 mol unknownmolar mass knownOROROther6.02 × 1023 particlesmol of unknownKnown L1 mol known22.4 L unknownORparticlesmol of known1 mol unknown22.4 L known6.02 × 1023 particles
35 Stoichiometry Problems How many moles of KClO3 must decompose in order to produce 9 moles of oxygen gas?2KClO3 2KCl + 3O2? mol9 mol9 mol O22 mol KClO33 mol O2= 6 molKClO3
36 Stoichiometry Problems How many grams of KClO3 are req’d to produce 9.00 L of O2 at STP?2KClO3 2KCl + 3O2? g9.00 L9.00 LO21 molO222.4 L2 molKClO33 molO2122.55g KClO31 molKClO3= 32.8 gKClO3
37 Stoichiometry Problems How many grams of silver will be formed from 12.0 g copper?Cu + 2AgNO3 2Ag + Cu(NO3)212.0 g? g12.0g Cu1 molCu63.55g Cu2 molAg1 molCu107.87g Ag1 molAg= 40.7 gAg
38 Stoichiometry Problems How many grams of Cu are required to react with 1.5 L of 0.10M AgNO3?Cu + 2AgNO3 2Ag + Cu(NO3)2? g1.5L0.10M1.5L.10 molAgNO31 L1 molCu2 molAgNO363.55g Cu1 molCu= 4.8 gCu