14 3 Review And Reinforcement Chemistry Answers

14 3 Review And Reinforcement Chemistry Answers 143 Review and Reinforcement Chemistry Answers This comprehensive guide provides detailed answers and explanations for the review and reinforcement questions found in Chapter 143 of your chemistry textbook Well cover key concepts calculations and problemsolving strategies to help you solidify your understanding of this important chapter Key Topics Covered Chemical Reactions and Stoichiometry Understanding the basics of chemical reactions balancing equations and calculating mole ratios Limiting Reactants and Percent Yield Determining the limiting reactant in a reaction and calculating theoretical and actual yields Solution Stoichiometry Applying stoichiometry to reactions involving solutions and determining concentrations Review and Reinforcement Questions and Answers 1 Define the following terms Chemical Reaction A process involving the rearrangement of atoms and molecules to form new substances Reactants The starting materials in a chemical reaction Products The substances formed in a chemical reaction Coefficient A number placed before a chemical formula in a balanced chemical equation representing the relative number of moles of that substance involved Stoichiometry The study of the quantitative relationships between reactants and products in chemical reactions 2 Balance the following chemical equations a 2 Na Cl 2 NaCl This equation represents the reaction between sodium and chlorine gas to produce sodium chloride The balanced equation indicates that two moles of sodium react with one mole of chlorine gas to produce two moles of sodium chloride 2 b CH 5 O 3 CO 4 HO This equation represents the combustion of propane CH with oxygen to produce carbon dioxide and water The balanced equation shows that one mole of propane reacts with five moles of oxygen to produce three moles of carbon dioxide and four moles of water c FeO 3 CO 2 Fe 3 CO This equation represents the reaction between iron oxide FeO and carbon monoxide CO to produce iron Fe and carbon dioxide CO The balanced equation indicates that one mole of iron oxide reacts with three moles of carbon monoxide to produce two moles of iron and three moles of carbon dioxide 3 Calculate the molar mass of the following compounds a HO 2 x 101 gmol 1 x 1600 gmol 1802 gmol b CO 1 x 1201 gmol 2 x 1600 gmol 4401 gmol c CaCO 1 x 4008 gmol 1 x 1201 gmol 3 x 1600 gmol 10009 gmol 4 How many grams of sodium chloride NaCl are produced when 250 g of sodium Na reacts completely with excess chlorine gas Cl 1 Write the balanced equation 2 Na Cl 2 NaCl 2 Calculate the molar mass of Na 2299 gmol 3 Calculate the moles of Na 250 g Na 2299 gmol 109 mol Na 4 Use the mole ratio from the balanced equation to find the moles of NaCl 109 mol Na x 2 mol NaCl 2 mol Na 109 mol NaCl 5 Calculate the mass of NaCl 109 mol NaCl x 5844 gmol 637 g NaCl 5 What is the limiting reactant when 100 g of hydrogen gas H reacts with 500 g of oxygen gas O 1 Write the balanced equation 2 H O 2 HO 2 Calculate the moles of H 100 g H 202 gmol 495 mol H 3 Calculate the moles of O 500 g O 3200 gmol 156 mol O 4 Determine the limiting reactant by comparing the mole ratio of reactants According to the balanced equation 2 moles of H react with 1 mole of O We have 495 moles of H and 156 moles of O To react completely with 495 moles of H we would need 248 moles of O 495 moles H x 1 mol O 2 mol H Since we only have 156 moles of O oxygen is the limiting reactant 6 Calculate the theoretical yield of water HO when 100 g of hydrogen gas H reacts 3 completely with excess oxygen gas O 1 Write the balanced equation 2 H O 2 HO 2 Calculate the moles of H 100 g H 202 gmol 495 mol H 3 Use the mole ratio from the balanced equation to find the moles of HO 495 mol H x 2 mol HO 2 mol H 495 mol HO 4 Calculate the mass of HO 495 mol HO x 1802 gmol 892 g HO 7 A chemist performs a reaction and obtains 750 g of product The theoretical yield for the reaction is 850 g What is the percent yield of the reaction Percent Yield Actual Yield Theoretical Yield x 100 Percent Yield 750 g 850 g x 100 882 8 A solution is made by dissolving 250 g of sodium chloride NaCl in enough water to make 5000 mL of solution What is the molarity of the solution 1 Calculate the moles of NaCl 250 g NaCl 5844 gmol 0427 mol NaCl 2 Convert the volume of solution to liters 5000 mL x 1 L 1000 mL 0500 L 3 Calculate the molarity Molarity moles of solute liters of solution Molarity 0427 mol NaCl 0500 L 0854 M 9 How many grams of calcium chloride CaCl are needed to make 2500 mL of a 0200 M solution 1 Convert the volume of solution to liters 2500 mL x 1 L 1000 mL 0250 L 2 Calculate the moles of CaCl needed 0250 L x 0200 molL 00500 mol CaCl 3 Calculate the mass of CaCl needed 00500 mol CaCl x 11098 gmol 555 g CaCl 10 A 250 mL sample of a 0100 M hydrochloric acid HCl solution is titrated with a 0150 M sodium hydroxide NaOH solution What volume of NaOH solution is required to reach the equivalence point 1 Write the balanced equation HCl NaOH NaCl HO 2 Calculate the moles of HCl 250 mL x 1 L 1000 mL x 0100 molL 000250 mol HCl 3 Use the mole ratio from the balanced equation to find the moles of NaOH 000250 mol HCl x 1 mol NaOH 1 mol HCl 000250 mol NaOH 4 Calculate the volume of NaOH solution needed 000250 mol NaOH 0150 molL 00167 L or 167 mL Conclusion 4 By working through these review and reinforcement questions you have gained a comprehensive understanding of key concepts and calculations related to chemical reactions and stoichiometry These concepts provide a foundation for further exploration in chemistry allowing you to predict the outcomes of reactions and understand the quantitative relationships involved Remember to practice solving different types of stoichiometry problems to solidify your understanding and build confidence in applying these important principles