Vocab Assignment Due: Quiz 1: Quiz 2: UT Quest Due: #1: #2: #3: Test Date:

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1 Honors Chemistry Unit 8 Chapter 9 Stoichiometry Unit 8 Packet Page 1 of 12 Vocab Assignment Due: Quiz 1: Quiz 2: UT Quest Due: #1: #2: #3: Test Date: VOCABULARY Assignment: 1) stoichiometry 4) percentage yield 7) mole ratio 2) massmass (gram to gram) problem 5) limiting reagent (reactant) 8) excess reagent 3) theoretical yield 6) actual yield (reactant) OBJECTIVES: Be able to do stoichiometry problems (massmass problems) Be able to calculate the limiting reagent for a given chemical reaction Be able to calculate percent yield Be able to correctly use a mole ratio Be able to write and balance chemical equations for use in stoichiometric problems Guided Notetaking Stoichiometry Stoichiometry Reaction Stoichiometry mass relationships between reactants and products in a chemical 0 rxn 0 Mole Ratio Mole ratio is determined from a balanced equation! Example: 2Al2O3 à 4Al + 3O2 mole ratios: decomposes 2 mol aluminum oxide Coefficients to form 4 mol Al and 3 mol 02 anathema ou 4 Theatres ; Tummy or Emmaus 4gmttt#ov3mol0z4mol A 1 Practice w/ mol to mol ratios Pg 277, #3

2 Unit 8 Packet Page 2 of 12 Reaction Stoichiometry Problems Given and an Unknown **Type 1: mol to mol problems " G " " W " 2AbOg 4A ,2 Example: Using the previous rxn, how many mol of Al can be produced from 13 mol of aluminum oxide? Tg Baathists 26mg Practice w/ mol to mol problems Pg 296 Inclass Problems 10a, 11a

3 **Type 2: mol to g problems Unit 8 Packet Page 3 of 12 LAKOG 4A 1 t 302 Example: Using the same rxn, how many g of O2 can be produced from 13 mol Al2O3? a '?g a 3mlTAHee#32&o2a624g@ Example: Using the same rxn, how many g of Al will be produced at the same time as 3 mol O2??gAl 8mdkhhlk#,10792gAC You Try Textbook, p 287 2a, b

4 **Type 3: g to mol problems Unit 8 Packet Page 4 of 12 AIZOZ Al /1* tn#xgf049molai IAKG 4AI +302 Example: Using the same rxn, how many mol of Al can be produced from 25g Al2O3? a?mo1al Example: Using the same rxn, how many mol of Al2O3 will be needed to produce 25 g Al? www05258#mmakytad0304baqql G? G You try: How many moles of salt can be formed from 120g of sodium reacting with Cl2? lmol Na 2Natcb 2NaC1 2mil/Vac1'209*#g*&qmued,NyaadO52molNaCT

5 **Type 4: g to g problems (aka mass to mass problems) Unit 8 Packet Page 5 of 12 a 2Ab% 4A I Example: Using the same rxn, how many g of Al can be produced from 25g Al2O3? T 2 ega 25NBHFI#gp*fAIgtxEffEl323sAT? G Example: Using the same rxn, how many g of Al2O3 will be needed to produce 25 g Al? yahoonet?#kia03kn9ffahiifna;2gg4gm You Try: Textbook, p 287, #4

6 Unit 8 Packet Page 6 of 12 Limiting Reagent (Reactant) (LR) Controls the amt of product formed Completely consumed in the rxn runs out first Example: People on plane à 300 people; 250 seats **Seats are the limiting factor** * Limiting Reagent Problems Do mass mass (g to g) calc for all reactants Whichever reactant produces the least is the Limiting Reagent (LR) Least amtis them you Make Can Example: If 50g of hydrogen reacts w/ 50g of oxygen to make water, which reactant is the LR? How much H2O is produced? atoa2hz05og5og7gh2oghzo5o09hzlg@gtykhg0f8ihyfg446gh20ojgho Practice pg 297 #26 a,c; Excess Reactant (ER) To find the amount of excess reactant leftover after a rxn: si#kee0d%efeah9!pyiaahw@hzsoybo91gakohb@349gaizgoy)3nac1tagn0pagutnan0z Do two massmass (g to g) problems to find LR Use LR to calculate excess reactant used Subtract excess reactant used from original amt of excess reactant leftover excess reactant ER Example: If 150g of salt (NaCl) reacts with 200g silver nitrate: a) How much AgCl is formed? 169g Agcl b) What is the limiting reagent? AGNO } c) How much of the excess reagent is left over? 150g?g 200g 8lgNa4Step1DoggwitheachreautantlamtprodncedttheoreticwDtsLMN@E4gAgal50gNa0HgMwllTatofI32nAgsYTe368gAgclAgNIYgAgok200gAyN03H03EhlY3qggllgfl69gAgIl6989gAyN0zStep2FUsethestartingamtof Practice p 297, 26b ( how continued much next excess page ) Limiting reactant to reactant was used find out

7 geese ms#imnmeam*ena69gnaclused in reaction Step 3 : Subtract amt of ER usged from initial amt Initial amt amt used Amt left over isognaa 699nA " Im ehgenanagr esgmamng)ht 26 b ( 297 p ) Ahab ogahatb%08fi#4eayyot8ohmeailohb 15,9g Al long used Excess 250g159g 91g AKOH }

8 Unit 8 Packet Page 7 of 12 LR ER If 130g of KOH reacts with 170g of Al(NO3)3: 3 KOH + AKNO )3 3KNOztAI(0H} a) How much KNO3 is produced? 23,45g, b) What is the limiting reagent? KOH c) How much of the excess reactant is left over? 05g AHNOD 3?gKNo5EF7 ex9@( tgknozekaskat#g&jkkn03hjn29eyyn0o3zi2345gkntf3mrlkoh BA#03*AtNBhkaNqEf2gknB21328gAIlN0D3 lmoekwlb sn#ttigoftoikhnoogh23e8gatwi2n2@ian0d3b qeiyn8k, Percent Yield Value % yield really he measured actual yield X 100% theoretical yield should have goltenoramt theoretical yield: n maximum amt of product n from massmass (g to g) problem Given starting Example: calc Tel actual yield: ( product!) n actual amt of product n from lab result; or given in a problem 170 ( 9 Excess possible ant 05 Using g g theoretical 165 the yield theoretical yield CO + 2H2 à CH3OH > 750g If 750g of CO reacts to produce 684g of CH3OH, what is the % yield? tgg#h75i0gkwlmwlut3oh/32gut30h85yg280lgc0fiutz0hat3oh9ogieldiaitaexioo68ietcsntohnydrentiaydmaag 857* %0 Practice pg 297 #26 a,c; pg 297 #28, 31

9 Stoichiometry Mole to Mole Problems Unit 8 Packet Page 8 of 12?molHz G 2MHHFis 6molH?mol0z 3mL 02 bmvlkcio#2nwlk40z 9molOz? t[ 3molznfIE lmolzn 3molH?mdq mvlkng 5mmol 02 4mtslt#tT 20mol KNO52mohttlw mil 2molk3PQHKNt36molKNOzllmvlkzp047mil lmolakhbzl } KNDZ

10 Stoichiometry Mass to Mass Problems Unit 8 Packet Page 9 of 12?gK µmol 1<403 Zmolkcl 12255gkagkmolkciq/Ymoe5?#5c1521gKCl?gHz50ogN4ymoeynz13,maeyhgpna6gHz_o1molHz1O79gH2?gnas5a09N2kytoIYnd9momYYnt3lYmhhIaozT&ggm+3?gAg450gAgN03pmdBgnNg03gpnmolAy4H3ngAgt lmdybltgagcl?gbaae5r0gbn9ymolbgnn03ngygmohebajtng)20828gba42_n mdAgN0} lmol Back 307g Back

11 Unit 8 Packet Page 10 of 12 Stoichiometry Worksheet #1 Perform the following calculations Be sure to use proper units! Answer the following g àmol and/or mol à g conversion problems 1 How many g in 700 mol of N2? 196GHz 7molNz 28i025N2_19bgNz lmolalz 2 How many g in 0455 mol of NaCl? 3 How many mol in 230 g of CaCO3? Answer questions 49 given the following equation 2AgNO3(aq) + Na2CO3(aq) à Ag2CO3(s) + 2NaNO3(aq)? 2%1 4 What is the ratio of mol of AgNO3 to mol of Ag2CO3? 1%2 5 What is the ratio of mol of Na2CO3 to mol of NaNO3? 2 :L 6 What is the ratio of mol of AgNO3 to mol of Na2CO3? 2 OOMDNAZCOZ 7 How many mol of Na2CO3 are required to produce 200 Mol of Ag2CO3? 2 0OmolAgzCO3 1molNazC03 It 150mA AGZCO } 8 How many mol of Ag2CO3 are produced from 300 mol of AgNO3? 3 00molAgNOz 1molAgzC0z t 9 How many g of Na2CO3 are required to produce 1 mol of Ag2CO3? zbbg/yac10i455molnacl/5844gna4_zb6gnag1molnac1o230molcacdz230gcat03ymolca03_o23omollo009gcac03cawz Answer questions 1013 given the following equation 3BaCl2(aq) + 2H3PO4(aq) à Ba3(PO4)2(s) + 6HCl(aq) 10 What is the mol ratio between BaCl2 and Ba3(PO4)2? 106gNazC0z1molAgzC04jmoedNngaz03qY05r99gNazc031mvlNazC0z3I1963gBazlP04tz@yyI3aYytEaYI3sogaa100gBaC1zYmolBa4z6molH43645gHC12o83gBaeMBa9imtt4jnlg 11 Given 100 g of BaCl2, how many g of Ba3(PO4)2 will be produced? Remember: gßàmolßàmolßàg 12 Given 100 g of BaCl2, how any g of HCl will be produced? 13 How many g of BaCl2 is required to produce 200g of HCl? wordpresshkmmn#92kme3sbaaii8 Back

12 Unit 8 Packet Page 11 of 12 Stoichiometry Worksheet #2 Perform the following calculations Be sure to use proper units! Write the equation for the reaction in chemical symbols when necessary, then answer the following massmass problems 1 (a) Write the equation for the synthesis of carbonic acid from water and carbon dioxide (b) Given 150 g of water and an excess of carbon dioxide, how much carbonic acid would be produced? 2(a) Write the decomposition reaction for sodium chloride (b) How many g of sodium chloride will produce 190 g of sodium? (c) How many g of chlorine will be produced from the conditions in (b)? HzOtCOzHaC03lgjsgHzcogl509HzMlmdzgtty0oYmdtt2C03fe203sHz03_g5t6gHzcglmoeHz01molHzC0z2NaC1so2NatClzMayaIYaalTIYlYbYa9t483gNa4m9NapIgYudIIalY@FIzg3gokQ13O 3 Given this equation: Al(NO3)3(aq) + 3NaOH(aq) à Al(OH)3(s) + 3NaNO3(aq) 1g 7801g 400g 8500g (a) If 150 g of aluminum nitrate reacts completely with sodium hydroxide, what would be the resulting mass of aluminum hydroxide? 150gAllN03by1mvlAIlNO3by1molAll0Hb7801gAKoHb213O1gAIlNO3blmrlA1lNO3H1mlAtt0H354qgAlloHlzsogawo3byIjhaygTtaYaEh95Hnno0sisognano3FoabYgaaYotfjFNaYoYH@Yoltaoo (b) Would be the resulting mass of sodium nitrate under the same conditions? (c) How many g of sodium hydroxide would be needed to form 130 g of aluminum hydroxide? at

13 STOICHIOMETRY PRACTICE Work problems on a separate piece of paper * solutions on next page Unit 8 Packet Page 12 of 12 you Remember: You must have 1556Gt correct, balanced equations to work these problems!! 1 In the synthesis reaction of iron (II) with sulfur, what mass of iron is needed to react completely with 320 g of sulfur? 2 Given: Zn + 2 HBr à ZnBr2 + H2 ; What mass of zinc bromide can be produced from 250 g of hydrobromic acid? 3 Silver bromide can be precipitated by the reaction of silver nitrate with sodium bromide What weight of precipitate can be produced starting with 343 g of sodium bromide? 4 Hydrochloric acid is added to 500 g of iron (II) sulfide What mass of hydrogen sulfide is produced? Given the Haber process: N2 + 3 H2 à 2NH3 If 341 g of hydrogen reacts with 22 g of nitrogen what is the limiting reagent? How much ammonia is produced? 62bg/AgB@NzisLR@27gN#g,clzisLR_ggcactheoreticalyieldl639gHzST9159opercentyield_ 6 When 25 g of calcium reacts with 25 g of chlorine, how much calcium chloride is produced? 7 In lab, you start with 128 g of sulfur dioxide to produce 150 g of sulfurous acid How much sulfurous acid should be produced and what is your percent yield? SO2 + H2O à H2SO3 348gZnBrz# must * show work on separate paper * Review Sheet Unit 6 Stoichiometry 1 Write a balanced equation for the reaction of aluminum nitrate with sodium hydroxide What type of rxn is this? 2 How many g of sodium hydroxide would be needed to from 130 g of Al(OH)3? 3 How many mol of aluminum hydroxide would be formed from 150 g of Al(NO3)3? 4 For the decomposition of mercury (II) oxide how many g of O2 are formed from 10 mol of HgO? 5 Given: C7H6O3 + CH3OH à C8H8O3 + H2O A chemist starts with 175 g of C7H6O3 and produces 142 g of C8H8O3 what is her percent yield? 6 Suppose a solution containing 350 g of sodium phosphate is mixed with a solution containing 640 g of barium nitrate How many grams of barium phosphate can be formed? Answers: 1 Al(NO3)3 + 3 NaOH à Al(OH)3 + 3 NaNO3 Double displacement g NaOH mol Al(OH) g O % g

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