BCLN CHEMISTRY 11 - Rev. July/2014 Unit 5 ~ Learning Guide Name: ______________________________ Instructions: Using a pencil, complete the following notes as you work through the related lessons. Show ALL work as is explained in the lessons. You are required to have this package completed BEFORE you write your unit test. Do your best and ask questions if you don’t understand anything! Chemical Equations: 1. What three things are conserved in a chemical reaction? The total number of each kind of atom The total mass The total energy 2. The reaction which powers the engine in a car is as follows: 2 C6H18 + 2 1O2 12 CO2 + 18 H2O A car burns 2000. g of octane gas (C8H18) and uses 7450. g of oxygen gas to do so. If this creates 5850. g of carbon dioxide then how many grams of water are created? 7450. g + 2000. g - 5850. g = 3600. g H2O Balancing Equations: 1. What must you NEVER change when balancing an equation? Subscripts 2. Fill in the following with the correct symbol. Phase Solid Liquid Gas Aqueous Symbol (s) (l) (g) (aq) Page 1 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 3. Balance the following equations by filling in the blanks with the correct coefficient. Use the table below each reaction to show your work. It is usually easiest to do the element found in the most compounds LAST and to start with the element that is simplest to balance. An example is provided for you. where H was balanced LAST and Al was balanced first. _1__Al4C3 + _12_H2O __3_CH4 + _4__Al(OH)3 Reactants Products Al 4 Al 1x4 = 4 C3 C 1x3 =3 H 2x12 = 24 H 4x3 =12 + 3x4 = 12 = 24 O 1x12 = 12 O 3x4 = 12 a) __1_Mg + __2_HCl __1_MgCl2 + __1_H2 Reactants Products Mg 1 Mg 1 H 1x2 = 2 H2 Cl 1x2 = 2 Cl 2 b) __2_BiCl3 + __3_H2S _1_Bi2S3 + __6_HCl Reactants Products Bi 1x 2 = 2 Bi 2 Cl 3 x 2 = 6 Cl 1 x 6 = 6 H 2x3 = 6 H 1x6=6 S 1x3 = 3 S3 c) __3_Fe + __2_O2 _1_Fe3O4 Reactants Products Fe 1x3 = 3 Fe 3 O 2x2=4 O4 Page 2 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 d) __2_H2O2 _2__H2O + __1_O2 Reactants Products H 2x2 = 4 H 2x2 = 4 O 2x2=4 O 1x2 =2 + 2 = 4 e) _2_K2CrO4 + _2__HCl __1_K2Cr2O7 + __2_KCl + __1_H2O Reactants Products K 2x2 = 4 K2 Cr 1x2 = 2 Cr 2 O 4x2 = 8 O7 H 1x2 =2 H2 Cl 1x2 = 2 Cl 1x2 = 2 f) __1_C6H12O6 + 1x2 = 2 = 4 + 1 = 8 + _6__O2 __6_CO2 + _6__H2O Reactants Products C6 C 1x6 = 6 H 12 H 2x6 = 12 O 6 + 2x6 = 12 = 18 O 2x6 = 12 + 1x6 = 6 = 18 g ) _2__C8H18 + _25_O2 _16__CO2 + _18__H2O Reactants Products C 8x2 = 16 C 1x16 = 16 H 18x2 = 36 H 2x18 = 36 O 2x25 = 50 O 2x16 = 32 + 1x18 = 18 = 50 Page 3 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 Types of Chemical Reactions: 1. What are the 6 types of reactions you are expected to be able to recognize in Chemistry 11? Combination (Synthesis), Decomposition, Single Replacement, Double Replacement, Combustion, Acid-Base (Neutralization) 2. Please classify the following reactions as one of the 6 types you have learned about. IF you want extra practice see if you can balance them as well. You may use the following abbreviations of the types: Syn, Dec, SR, DR, Comb, Neut. a) ________Dec______ _2_ H2 O2 _2_ H2O + _1_O2 b) _______Neut______ _1_HCl + _1_ NaOH _1_NaCl +_1_H2O c) _________SR______ _2_Al + _3_ NiBr2 _2_AlBr3 + _3_Ni d) ________Syn______ _1_N2 + _3_ H2 _2_ NH3 e) _________DR_____ _1_AgNO3 + _1_ KCl _1_ AgCl + _1_ KNO3 f) _______Comb_____ _2_ C6H6 + _15_ O2 _12_ CO2 + _6_ H2O g) _________SR_____ _1_Mg + _2_ HCl _1_ MgCl2 + _1_ H2 h) ________Syn______ _3_ Mg + _1_ N2 _1_ Mg3N2 i) _________SR______ _1_ Ba + _2_ HBr _1_ BaBr2 + _1_ H2 j) _________DR______ _2_ BiCl3 + _3_ H2S _1_ Bi2S3 + _6_ HCl k) _________SR______ _1_ Br2 + _2_ KI _1_ I2 + _2_ KBr l) _________Syn_____ _3_ Fe + _2_ O2 _1_ Fe3O4 m) _______Comb_____ _2_ C4H10 + _13_ O2 _8_ CO2 + _10_ H2O n) _________SR______ _2_ CaO + _4_ C _2_ CaC2 + _1_ O2 o) ________Neut_____ _1_ LiOH + _1_ HBr _1_ LiBr + _1_ H2O p) _________SR______ _1_ Bi2O3 + _3_ H2 _2_ Bi + _3_ H2O q) ________Syn______ _1_ P4 + _6_ I2 _4_ PI3 Page 4 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 r) _______SR_______ _2_ Fe2O3 + _3_ C _4_ Fe + _3_ CO2 s) _______Comb_____ _1_ C6H12O6 + _6_ O2 _6_ CO2 + _6_ H2O t) _______Dec_______ _1_ NH4NO3 _1_ N2O + _2_ H2O u) _______DR_______ _1_ Al4C3 + _12_ H2O _3_ CH4 + _4_ Al(OH)3 v) _______Syn_______ _1_ Ca(OH)2 + _2_ CO2 _1_ Ca(HCO3)2 Note that balancing is optional for students on this question. Energy: 1. State whether each of the following are exothermic or endothermic. Reaction or Event Exo or Endo 2 C8H18 + 25 O2 16 CO2 + 16 H2O + 10110 kJ Exo Ba(OH)2 + 2 NH4Cl + 430 kJ BaCl2 + 2 NH4OH 6SOCl2 + CoCl26H2O CoCl2 + 12HCl + 6SO2 Mn(s) + 2 HCl(aq) MnCl2(aq) + H2(g) H = +360 kJ H = -221 kJ Endo Endo Exo Boiling Water Endo Metabolizing Food Exo The energy possessed by the products is greater than the energy possessed by the reactants. Endo 2. How much heat is evolved when 30.g of magnesium is burned in excess oxygen gas given the reaction below: 2Mg + O2 2 MgO 𝟑𝟎. 𝐠 𝐌𝐠 𝐱 𝟏 𝐦𝐨𝐥 𝐌𝐠 𝟐𝟒.𝟑𝟏 𝐠 𝐌𝐠 H = -600. kJ 𝐱 𝟔𝟎𝟎 𝐤𝐉 𝟐 𝐦𝐨𝐥 𝐌𝐠 = 𝟑𝟕𝟎 𝐤𝐉 Page 5 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 Stoichiometry: 1. Use the balanced equation below to answer the following questions. 1 Mg + 2 HCl 1 MgCl2 + 1 H2 a) How many moles of hydrogen gas are produced when 10 moles of hydrochloric acid completely react? 𝟏𝟎 𝐦𝐨𝐥 𝐇𝐂𝐥 𝐱 𝟏 𝐦𝐨𝐥 𝐇𝟐 = 𝟓 𝐦𝐨𝐥 𝐇𝟐 𝟐 𝐦𝐨𝐥 𝐇𝐂𝐥 b) What mass of magnesium chloride is produced if 5.75 mol of magnesium reacts completely? Molar Mass of MgCl2 = 1 Mg + 2 Cl = 1(24.31) + 2(35.45) = 95.21 g/mol 𝟓. 𝟕𝟓 𝐦𝐨𝐥 𝐌𝐠 𝐱 𝟏 𝐦𝐨𝐥 𝐌𝐠𝐂𝐥𝟐 𝟏 𝐦𝐨𝐥 𝐌𝐠 𝐱 𝟗𝟓.𝟐𝟏𝐠 𝐌𝐠𝐂𝐥𝟐 𝟏 𝐦𝐨𝐥 𝐌𝐠𝐂𝐥𝟐 = 𝟓𝟒𝟕𝐠 𝐌𝐠𝐂𝐥𝟐 c) What mass of magnesium is needed to react 15.2g of hydrochloric acid? Molar Mass of HCl = 1 H + 1 Cl = 1(1.01) + 1(35.45) = 36.46 g/mol 𝟏𝟓. 𝟐𝐠 𝐇𝐂𝐥 𝐱 𝟏 𝐦𝐨𝐥 𝐇𝐂𝐥 𝟑𝟔.𝟒𝟔𝐠 𝐇𝐂𝐥 𝐱 𝟏 𝐦𝐨𝐥 𝐌𝐠 𝟐 𝐦𝐨𝐥 𝐇𝐂𝐥 𝐱 𝟐𝟒.𝟑𝟏 𝐠 𝐌𝐠 𝟏 𝐦𝐨𝐥 𝐌𝐠 = 𝟓. 𝟎𝟕𝐠 𝐌𝐠 d) What mass of magnesium is needed to create 87.5 L of hydrogen gas at SATP? 𝟖𝟕. 𝟓𝐋 𝐇𝟐 𝐱 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝟐𝟒.𝟖𝐋 𝐇𝟐 𝐱 𝟏 𝐦𝐨𝐥 𝐌𝐠 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝐱 𝟐𝟒.𝟑𝟏 𝐠 𝐌𝐠 𝟏 𝐦𝐨𝐥 𝐌𝐠 = 𝟖𝟓. 𝟖𝐠 𝐌𝐠 e) How many molecules of hydrogen gas are created if 6.6 mol of hydrochloric acid react with 3.3 mol of magnesium? 𝟔. 𝟔 𝐦𝐨𝐥 𝐇𝐂𝐥 𝐱 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝟐 𝐦𝐨𝐥 𝐇𝐂𝐥 𝐱 𝟔.𝟎𝟐𝐱𝟏𝟎𝟐𝟑 𝐦𝐨𝐥𝐞𝐜𝐮𝐥𝐞𝐬 𝐇𝟐 𝟏 𝐦𝐨𝐥 𝐇𝟐 Page 6 of 12 = 𝟐. 𝟎𝐱𝟏𝟎𝟐𝟒 𝐦𝐨𝐥𝐞𝐜𝐮𝐥𝐞𝐬 𝐇𝟐 BCLN CHEMISTRY 11 - Rev. July/2014 2. Use the balanced equation below to answer the following questions. 2 C8H18(l) + 25 O2(g) 16 CO2(g) + 18 H2O(l) + 10110 kJ a) How many moles of water are created when 108 moles of oxygen gas completely react? 𝟏𝟎𝟖 𝐦𝐨𝐥 𝐎𝟐 𝐱 𝟏𝟖 𝐦𝐨𝐥 𝐇𝟐 𝐎 = 𝟕𝟕. 𝟖 𝐦𝐨𝐥 𝐇𝟐 𝐎 𝟐𝟓 𝐦𝐨𝐥 𝐎𝟐 b) How many litres of carbon dioxide gas will be created with 525 L of oxygen gas react completely at STP? Hint this can be done with a single conversion! 𝟓𝟐𝟓 𝐋 𝐎𝟐 𝐱 𝟏𝟔 𝐋 𝐂𝐎𝟐 𝟐𝟓 𝐋 𝐎𝟐 = 𝟑𝟑𝟔𝐋 𝐂𝐎𝟐 c) How much energy is created if a sample of C8H18 containing 7.63 x 1025 atoms of hydrogen reacts completely? 𝟕. 𝟔𝟑𝐱𝟏𝟎𝟐𝟓 𝐚𝐭𝐨𝐦𝐬 𝐇 𝐱 𝟏 𝐦𝐨𝐥𝐞𝐜𝐮𝐥𝐞 𝐂𝟖 𝐇𝟏𝟖 𝟏𝟖 𝐚𝐭𝐨𝐦𝐬 𝐇 𝐱 𝟏 𝐦𝐨𝐥 𝐂𝟖 𝐇𝟏𝟖 𝟔.𝟎𝟐𝐱𝟏𝟎𝟐𝟑 𝐦𝐨𝐥𝐞𝐜𝐮𝐥𝐞 𝐂𝟖 𝐇𝟏𝟖 𝐱 𝟏𝟎𝟏𝟏𝟎 𝐤𝐉 𝟐 𝐦𝐨𝐥 𝐂𝟖 𝐇𝟏𝟖 = 𝟑. 𝟓𝟔𝐱𝟏𝟎𝟒 𝐤𝐉 d) What volume of carbon dioxide gas at SATP is created in a reaction which produces 5.37x106 kJ of energy? 𝟓. 𝟑𝟕𝐱𝟏𝟎𝟔 𝐤𝐉 𝐱 𝟏𝟔 𝐦𝐨𝐥 𝐂𝐎𝟐 𝟏𝟎𝟏𝟏𝟎 𝐤𝐉 𝐱 𝟐𝟒.𝟖 𝐋 𝐂𝐎𝟐 𝟏 𝐦𝐨𝐥 𝐂𝐎𝟐 = 2.11x𝟏𝟎𝟓 𝐋 𝐂𝐎𝟐 e) What mass of octane gas (C8H18) is required to create 112 g of water? Molar Mass C8H18 = 8 C + 18 H = 8(12.01) + 18(1.01) = 114.26 g/mol Molar Mass H2O = 2 H + 1 O = 2(1.01) + 16.00 = 18.02 g/mol 𝟏𝟏𝟐𝐠 𝐇𝟐 𝐎 𝐱 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝐎 𝟏𝟖.𝟎𝟐𝐠 𝐇𝟐 𝐎 𝐱 𝟐 𝐦𝐨𝐥 𝐂𝟖 𝐇𝟏𝟖 𝟏𝟖 𝐦𝐨𝐥 𝐇𝟐 𝐎 𝐱 𝟏𝟏𝟒.𝟐𝟔𝐠 𝐂𝟖 𝐇𝟏𝟖 𝟏 𝐦𝐨𝐥 𝐂𝟖 𝐇𝟏𝟖 Page 7 of 12 = 𝟕𝟖. 𝟗𝐠 𝐂𝟖 𝐇𝟏𝟖 BCLN CHEMISTRY 11 - Rev. July/2014 3. To do each of these questions you will need the result from the previous question. The answers for each are provided but please do your best to try and do them on your own before checking the answers. a) If barium hydroxide reacts with ammonium nitrate what type of reaction is occurring? double replacement b) What are the names of the two products of this reaction? barium nitrate and ammonium hydroxide c) Write and then balance the equation for this reaction. Remember you need to make sure to correctly balance each ion with each other to create the correct chemical formulas. Ba(OH)2 + 2 NH4NO3 Ba(NO3)2 + 2 NH4OH d) What mass of ammonium hydroxide is created if 26.4g of barium hydroxide reacts completely? Molar Mass Ba(OH)2 = 1 Ba + 2 O + 2 H = 1(137.33) + 2(16.00) + 2(1.01) = 171.35 g/mol Molar Mass NH4OH = 1 N + 5H + 1 O = 1(14.01) + 5(1.01) + 1(16.00) = 35.06 g/mol 𝟐𝟔. 𝟒𝐠 𝐁𝐚(𝐎𝐇)𝟐 𝐱 𝟏 𝐦𝐨𝐥 𝐁𝐚(𝐎𝐇)𝟐 𝟏𝟕𝟏.𝟑𝟓𝐠 𝐁𝐚(𝐎𝐇)𝟐 𝐱 𝟐 𝐦𝐨𝐥 𝐍𝐇𝟒 𝐎𝐇 𝟏 𝐦𝐨𝐥 𝐁𝐚(𝐎𝐇)𝟐 𝐱 𝟑𝟓.𝟎𝟔𝐠 𝐍𝐇𝟒 𝐎𝐇 𝟏 𝐦𝐨𝐥 𝐍𝐇𝟒 𝐎𝐇 = 𝟏𝟎. 𝟖𝐠 𝐍𝐇𝟒 𝐎𝐇 e) If 37.4 kJ of energy are required for every 2 moles of ammonium nitrate that react how much energy is required to cause 48.6g of ammonium nitrate to react completely? Molar Mass NH4 NO3 = 2 N + 4H + 3 O = 2(14.01) + 4(1.01) + 3(16.00) = 80.06 g/mol 𝟒𝟖. 𝟔𝐠 𝐍𝐇𝟒 𝐍𝐎𝟑 𝐱 𝟏 𝐦𝐨𝐥 𝐍𝐇𝟒 𝐍𝐎𝟑 𝟖𝟎.𝟎𝟔𝐠 𝐍𝐇𝟒 𝐍𝐎𝟑 𝐱 𝟑𝟕.𝟒 𝐤𝐉 𝟐 𝐦𝐨𝐥 𝐍𝐇𝟒 𝐍𝐎𝟑 Page 8 of 12 = 𝟏𝟏. 𝟒 𝐤𝐉 BCLN CHEMISTRY 11 - Rev. July/2014 Limiting Reagents: 1. Define the following terms and provide the formula for the third. a) Limiting Reagent - The reactant in a reaction that runs out or is totally consumed b) Excess Reagent - The reactant in a reaction that remains after the reaction is complete c) Percent Yield - a measure of how much product was actually obtained in an experiment compared to how much was predicted to be made 𝐏𝐞𝐫𝐜𝐞𝐧𝐭 𝐘𝐢𝐞𝐥𝐝 = 𝐀𝐜𝐭𝐮𝐚𝐥 𝐘𝐢𝐞𝐥𝐝 𝐓𝐡𝐞𝐨𝐫𝐞𝐭𝐢𝐜𝐚𝐥 𝐘𝐢𝐞𝐥𝐝 𝐱𝟏𝟎𝟎% 2. Consider the following reaction: 2Al + 3 NiBr2 2 AlBr3 + 3 Ni. 27.0 g of aluminum react with 219 g nickel (II) bromide. a) Which reactant is the limiting reagent? Show your work! 1. Moles of Al present: 27.0 g Al 1 mol Al 1.00 mol Al is present 26.98 g Al 2. Moles of NiBr2 present: Molar Mass of NiBr2 = 1 Ni + 2 Br = 1(58.69) + 2(79.90) = 218.49 g/mol 219 g NiBr2 1 mol NiBr2 1.00 mol NiBr2 is present 218.49 g NiBr2 3. Moles of NiBr2 required to react with all the Al present: 1.00 mol Al 3 mol NiBr2 1.50 mol NiBr2 is required 2 mol Al 4. Because Moles NiBr2 present < Moles of NiBr2 required, NiBr2 is the Limiting Reagent Page 9 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 b) What mass of excess reagent is left over when the reaction is complete Moles Excess Reagent Limiting Reagent Product Product 2Al 3NiBr2 2AlBr3 3Ni initial moles change in moles final moles 1.00 - 0.667 0.333 1.00 - 1.00 0 0 +0.667 0.667 0 +1.00 1.00 × 2/3 × 2/3 Mass of Excess Reagent (Al) left over: 0.333 mol Al 26.98 g Al 8.98 g Al 1 mol Al c) What mass of aluminum bromide is created in the reaction? Be sure to use the limiting reagent in this calculation Molar Mass of AlBr3 = 1 Al + 3 Br = 1(26.98) + 3(79.90) = 266.68 g/mol Mass of AlBr3 created = 0.667 mol AlBr3 266.68 g AlBr3 178 g AlBr3 1 mol AlBr3 3. Answer these questions based on this reaction and the following information Mn(s) + 2 HCl(aq) MnCl2(aq) + H2(g) H = -221 kJ 115g of manganese is placed in a 1.25 L of a 3.50 M solution of hydrochloric acid. a) Which reactant is the limiting reagent? Show your work! 1. Moles of Mn present: 115 g Mn 1 mol Mn 2.093 mol Mn is present 54.94 g Mn 2. Moles of HCl present: 3.50 mol HCl 1.25 L 4.375 mol HCl is present 1L 3. Moles of HCl required to react with all the Mn present: 2.093 mol Mn 2 mol HCl 4.186 mol HCl is required 1 mol Mn 4. Because Moles of HCl present > Moles of HCl required, HCl is the Excess Reagent. Therefore, Mn is the Limiting Reagent. Page 10 of 12 BCLN CHEMISTRY 11 - Rev. July/2014 b) How many moles of excess reagent is left over when the reaction is complete? Moles Limiting Reagent Excess Reagent Mn 2HCl Product Product MnCl2 H2 initial moles 2.093 × 2/1 4.375 0 change in moles 2.093 4.186 +2.093 c) What is the theoretical mass of hydrogen gas created in the reaction? final moles 0 0.189 2.093 0 +2.093 2.093 Moles of Excess Reagent (HCl) Left over = 0.189 moles c) What is the theoretical mass of hydrogen gas created in the reaction? Theoretical Mass of H2(g): 2.093 mol H 2 2.02 g H 2 4.23 g H 2 1 mol H 2 d) If 33.6 L of hydrogen gas was measured to have formed at STP what is the percent yield of this reaction? Hint: You will need to convert this amount to grams! 𝐀𝐜𝐭𝐮𝐚𝐥 𝐘𝐢𝐞𝐥𝐝 = 𝟑𝟑. 𝟔𝐋 𝐇𝟐 𝐱 𝐏𝐞𝐫𝐜𝐞𝐧𝐭 𝐘𝐢𝐞𝐥𝐝 = 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝟐𝟐.𝟒 𝐋 𝐇𝟐 𝐀𝐜𝐭𝐮𝐚𝐥 𝐘𝐢𝐞𝐥𝐝 𝐓𝐡𝐞𝐨𝐫𝐞𝐭𝐢𝐜𝐚𝐥 𝐘𝐢𝐞𝐥𝐝 𝐱 𝟐.𝟎𝟐𝐠 𝐇𝟐 𝟏 𝐦𝐨𝐥 𝐇𝟐 𝐱𝟏𝟎𝟎% = Answers: Chemical Equations: 2. 3600. g H2O Balancing Equations: 3. a) 1,2,1,1 e) 2, 2,1,2,1 b) 2,3,1,6 c) 3,2,1 f) 1,6,6,6 g) 2,25,16,18 d) 2, 2, 1 Page 11 of 12 = 𝟑. 𝟎𝟑𝐠 𝐇𝟐 𝟑.𝟎𝟑𝐠 𝐇𝟐 𝟒.𝟐𝟑𝐠 𝐇𝟐 𝐱𝟏𝟎𝟎% = 𝟕𝟏. 𝟔% BCLN CHEMISTRY 11 - Rev. July/2014 Energy 2. 370 kJ Stoichiometry 1. a) 5 mol H2 b) 547g MgCl2 c) 5.07g Mg e) 2.0 x 1024 molecules H2 d) 85.8g Mg 2. a) 77.8 mol H2O b) 336 L CO2 d) 2.11 x 105 L CO2 3. a) double replacement c) 3.56 x 104 kJ e) 78.9g C8H18 b) barium nitrate and ammonium hydroxide c) Ba(OH)2 + 2 NH4NO3 Ba(NO3)2 + 2 NH4OH d) 10.8 g NH4OH e) 11.4 kJ Limiting Reagents: 2. a) NiBr2 b) 8.98 g Al c) 178 g AlBr3 3. a) Mn b) 0.189 mol HCl c) 4.23 g H2 Page 12 of 12 d) 71.6%