A research paper states that a novel synthesis of quinine started with 500 g of a precursor (MW = 200.0 g/mol) and produced 55.0 g of quinine (MW = 324.42 g/mol). The balanced equation shows a 1:1 mole ratio between precursor and product (quinine). Calculate the percent yield for this reaction?

Question 1

Answer · 2026-06-18T23:40:30.214Z

Here are the solutions to the chemistry questions. e) To calculate the percent yield for the reaction: Step 1: Calculate the moles of the precursor. Moles of precursor = Mass of precursorMW of precursor = 50.0 g200.0 g/mol = 0.250 mol Step 2: Determine the theoretical moles of quinine using the 1:1 mole ratio. Theoretical moles of quinine = 0.250 mol Step 3: Calculate the theoretical mass of quinine. Theoretical mass of quinine = Theoretical moles × MW of quinine Theoretical mass of quinine = 0.250 mol × 324.42 g/mol = 81.105 g Step 4: Calculate the percent yield. Percent Yield = Actual YieldTheoretical Yield × 100\% Percent Yield = 55.0 g81.105 g × 100\% = 67.813\% Rounding to three significant figures: Percent Yield = 67.8\% The percent yield for this reaction is 67.8\%. a) To separate two miscible liquids with different boiling points (50°C and 110°C), fractional distillation is the appropriate technique. Description of separation: The mixture of liquids A (boiling point 50°C) and B (boiling point 110°C) is heated in a distillation flask. As the temperature increases, liquid A, having the lower boiling point, will vaporize preferentially. The vapor rises into a fractionating column, where it undergoes repeated cycles of vaporization and condensation, becoming progressively richer in liquid A. This enriched vapor then passes into a condenser, where it cools and condenses back into liquid form, which is collected in a receiving flask. Liquid B, with the higher boiling point, remains predominantly in the distillation flask. Diagram of equipment setup: A diagram would typically include: • A round-bottom distillation flask containing the mixture, heated by a heating mantle or Bunsen burner. • A fractionating column (e.g., packed with glass beads or rings) attached vertically above the flask. • A thermometer placed at the top of the fractionating column to measure the temperature of the vapor distilling over. • A condenser (e.g., Liebig condenser) connected to the side arm of the fractionating column, with water flowing through its jacket to cool the vapor. • A receiving flask or beaker to collect the distillate, placed at the end of the condenser. b) To show that Carbon Monoxide (CO) and Carbon Dioxide (CO₂) obey the Law of Multiple Proportions: Step 1: Determine the mass of oxygen that combines with a fixed mass of carbon in each compound. Let's fix the mass of carbon at 12.01 g (1 mole of carbon). • In Carbon Monoxide (CO): 1 mole of carbon (12.01 g) combines with 1 mole of oxygen (16.00 g). • In Carbon Dioxide (CO₂): 1 mole of carbon (12.01 g) combines with 2 moles of oxygen (2 × 16.00 g = 32.00 g). Step 2: Calculate the ratio of the masses of oxygen. The masses of oxygen combining with 12.01 g of carbon are 16.00 g (in CO) and 32.00 g (in CO₂). Ratio of oxygen masses = Mass of O in CO_2Mass of O in CO = 32.00 g16.00 g = (2)/(1) Since the ratio of the masses of oxygen that combine with a fixed mass of carbon is 2:1, which is a ratio of small whole numbers, these compounds obey the Law of Multiple Proportions. c) The systematic names for the given compounds are: i) MgBr₂: Magnesium Bromide ii) Al₂O₃: Aluminum Oxide iii) FeCl₃: Iron(III) Chloride iv) CuO: Copper(II) Oxide v) N₂O₄: Dinitrogen Tetroxide vi) SF₆: Sulfur Hexafluoride vii) ClO₂: Chlorine Dioxide viii) PCl₅: Phosphorus Pentachloride ix) BaCl₂·2H₂O: Barium Chloride Dihydrate d) Balance each equation and identify the type of reaction: i) The equation Al_2(CO_3)_3 → Al_2O_3 + CO cannot be balanced as written for a simple decomposition. If we assume oxygen gas is also a product, it can be balanced as: 2Al_2(CO_3)_3 → 2Al_2O_3 + 6CO + 3O_2 Type of reaction: Decomposition reaction ii) BaO_2 + H_2SO_4 → BaSO_4 + H_2O_2 This equation is already balanced as written. Type of reaction: Double Displacement reaction iii) Ba(ClO_3)_2 → BaCl_2 + 3O_2 Type of reaction: Decomposition reaction iv) 3Cu + 8HNO_3 → 3Cu(NO_3)_2 + 2NO + 4H_2O Type of reaction: Redox reaction v) The equation H_3BO_3 → H_4B_4O_11 + H_2O cannot be balanced as written. The stoichiometry of atoms does not allow for a balanced equation with these specific products. vi) 10P_2I_4 + 13P_4 + 128H_2O → 40PH_4I + 32H_3PO_4 Type of reaction: Redox reaction

Question 2

Here are the solutions to the chemistry questions. e) To calculate the percent yield for the reaction: Step 1: Calculate the moles of the precursor. Moles of precursor = Mass of precursorMW of precursor = 50.0 g200.0 g/mol = 0.250 mol Step 2: Determine the theoretical moles of quinine using the 1:1 mole ratio. Theoretical moles of quinine = 0.250 mol Step 3: Calculate the theoretical mass of quinine. Theoretical mass of quinine = Theoretical moles × MW of quinine Theoretical mass of quinine = 0.250 mol × 324.42 g/mol = 81.105 g Step 4: Calculate the percent yield. Percent Yield = Actual YieldTheoretical Yield × 100\% Percent Yield = 55.0 g81.105 g × 100\% = 67.813\% Rounding to three significant figures: Percent Yield = 67.8\% The percent yield for this reaction is 67.8\%. a) To separate two miscible liquids with different boiling points (50°C and 110°C), fractional distillation is the appropriate technique. Description of separation: The mixture of liquids A (boiling point 50°C) and B (boiling point 110°C) is heated in a distillation flask. As the temperature increases, liquid A, having the lower boiling point, will vaporize preferentially. The vapor rises into a fractionating column, where it undergoes repeated cycles of vaporization and condensation, becoming progressively richer in liquid A. This enriched vapor then passes into a condenser, where it cools and condenses back into liquid form, which is collected in a receiving flask. Liquid B, with the higher boiling point, remains predominantly in the distillation flask. Diagram of equipment setup: A diagram would typically include: • A round-bottom distillation flask containing the mixture, heated by a heating mantle or Bunsen burner. • A fractionating column (e.g., packed with glass beads or rings) attached vertically above the flask. • A thermometer placed at the top of the fractionating column to measure the temperature of the vapor distilling over. • A condenser (e.g., Liebig condenser) connected to the side arm of the fractionating column, with water flowing through its jacket to cool the vapor. • A receiving flask or beaker to collect the distillate, placed at the end of the condenser. b) To show that Carbon Monoxide (CO) and Carbon Dioxide (CO₂) obey the Law of Multiple Proportions: Step 1: Determine the mass of oxygen that combines with a fixed mass of carbon in each compound. Let's fix the mass of carbon at 12.01 g (1 mole of carbon). • In Carbon Monoxide (CO): 1 mole of carbon (12.01 g) combines with 1 mole of oxygen (16.00 g). • In Carbon Dioxide (CO₂): 1 mole of carbon (12.01 g) combines with 2 moles of oxygen (2 × 16.00 g = 32.00 g). Step 2: Calculate the ratio of the masses of oxygen. The masses of oxygen combining with 12.01 g of carbon are 16.00 g (in CO) and 32.00 g (in CO₂). Ratio of oxygen masses = Mass of O in CO_2Mass of O in CO = 32.00 g16.00 g = (2)/(1) Since the ratio of the masses of oxygen that combine with a fixed mass of carbon is 2:1, which is a ratio of small whole numbers, these compounds obey the Law of Multiple Proportions. c) The systematic names for the given compounds are: i) MgBr₂: Magnesium Bromide ii) Al₂O₃: Aluminum Oxide iii) FeCl₃: Iron(III) Chloride iv) CuO: Copper(II) Oxide v) N₂O₄: Dinitrogen Tetroxide vi) SF₆: Sulfur Hexafluoride vii) ClO₂: Chlorine Dioxide viii) PCl₅: Phosphorus Pentachloride ix) BaCl₂·2H₂O: Barium Chloride Dihydrate d) Balance each equation and identify the type of reaction: i) The equation Al_2(CO_3)_3 → Al_2O_3 + CO cannot be balanced as written for a simple decomposition. If we assume oxygen gas is also a product, it can be balanced as: 2Al_2(CO_3)_3 → 2Al_2O_3 + 6CO + 3O_2 Type of reaction: Decomposition reaction ii) BaO_2 + H_2SO_4 → BaSO_4 + H_2O_2 This equation is already balanced as written. Type of reaction: Double Displacement reaction iii) Ba(ClO_3)_2 → BaCl_2 + 3O_2 Type of reaction: Decomposition reaction iv) 3Cu + 8HNO_3 → 3Cu(NO_3)_2 + 2NO + 4H_2O Type of reaction: Redox reaction v) The equation H_3BO_3 → H_4B_4O_11 + H_2O cannot be balanced as written. The stoichiometry of atoms does not allow for a balanced equation with these specific products. vi) 10P_2I_4 + 13P_4 + 128H_2O → 40PH_4I + 32H_3PO_4 Type of reaction: Redox reaction

A research paper states that a novel synthesis of quinine started with 500 g of a precursor (MW = 200.0 g/mol) and produced 55.0 g of quinine (MW = 324.42 g/mol). The balanced equation shows a 1:1 mole ratio between precursor and product (quinine). Calculate the percent yield for this reaction?

Still stuck on this one?

More Chemistry Questions