Aristo Book 5 Experiment Answer Essay Essays

Aristo Book 5 Experiment Answer Essay Essays Aristo Book 5 Experiment Answer Essay Essay Aristo Book 5 Experiment Answer Essay Essay HKDSE CHEMISTRY – A Modern View ( Chemistry ) Experiment Workbook 5 Suggested replies Chapter 52 Importance of industrial procedures Chapter 53 Rate equation Experiment 53. 1 Determining the rate equation of a reaction utilizing method of initial rate ( A microscale experiment ) 1 Chapter 54 Activation energy Experiment 54. 1 Determining the activation energy of a chemical reaction 3 Chapter 55 Catalysis and industrial procedures Experiment 55. 1 Investigating the action of a accelerator 6 Experiment 55. 2 Investigating homogenous contact action 8 Experiment 55. 3Investigating ways to alter the rate of a reaction with a suited accelerator 9 Experiment 55. 3 Sample laboratory study 13 Experiment 55. 4Preparing ethyl alcohol by agitation 16 Chapter 56 Industrial procedures Chapter 57 Green chemical science for industrial procedures Chapter 53Rate equation Experiment 53. 1Determining the rate equation of a reaction utilizing method of initial rate ( A microscale experiment ) 7. and 11. ( a ) Well figure 1 2 3 4 5 6 7 8 Number of beads of 0. 5 M Na2S2O3 ( aq ) 10 9 8 7 6 5 4 3 Time. T ( s ) 14. 2 15. 8 17. 8 20. 4 23. 8 28. 6 35. 7 47. 6 ( s?1 ) 0. 070 0. 063 0. 056 0. 049 0. 042 0. 035 0. 028 0. 021 10. and 12. ( a ) Well figure 1 2 3 4 5 6 7 8 Number of beads of 1. 0 M H2SO4 ( aq ) 10 9 8 7 6 5 4 3 Time. T ( s ) 59. 4 59. 7 60. 0 60. 7 59. 9 60. 0 61. 0 60. 5 ( s?1 ) 0. 017 0. 017 0. 017 0. 016 0. 017 0. 017 0. 016 0. 017 11. ( a ) reciprocally ( B ) ( degree Celsius ) 1 12. ( B ) 0 ( degree Celsius ) From the consequences in Table 53. 2. the readings of clip are near. bespeaking that the reaction is of zeroth order with regard to H+ ( aq ) . 13. Rate = k [ S2O32? ( aq ) ] 14. S2O32? ( aq ) + 2H+ ( aq ) ? S ( s ) + SO2 ( g ) + H2O ( cubic decimeter ) 15. In this experiment. the clip for the formation of a fixed. but little sum of indissoluble sulfur precipitate is measured. The shorter the clip. the faster is the reaction. It is assumed that the extent of reaction is still little when the clip is recorded. so that the clip recorded can be used as a measuring of initial rate of the reaction. Chapter 54Activation Energy Experiment 54. 1Determining the activation energy of a chemical reaction 5. Temperature of the reaction mixture (  °C ) 15 25 35 45 55 Time for the visual aspect of dark bluish coloring material ( s ) 679 ( at 11 °C ) 232 ( at 27 °C ) 112 ( at 37 °C ) 80 ( at 43 °C ) 33 ( at 56 °C ) 6. ( a ) rate changeless ; activation energy ; Universal gas invariable ; temperature ; ( B ) log ( ) ?2. 83 ?2. 37 ?2. 05 ?1. 90 ?1. 52 3. 52 3. 33 3. 23 3. 16 3. 04 ( degree Celsius ) ( vitamin D ) ?2750 ( vitamin E ) incline = ?2750 = Ea = 2750 ? 2. 3 ? 8. 314 J mol?1 = 52 586 J mol?1 = 52. 6 kJ mol?1 7. Arrhenius equation ; log k = log A 8. consecutive line ; 9. S2O82? ( aq ) + 2I? ( aq ) ? 2SO42? ( aq ) + I2 ( aq ) 10. To supervise the formation of I from the reaction of S2O82? ( aq ) ions and I? ( aq ) ions. 11. When all S2O82? ( aq ) ions have reacted. any I formed will turn the starch solution dark blue. The clip for this coloring material alteration is a step of the rate of reaction shown in inquiry 9. ( Note: The reaction rate is reciprocally relative to the clip taken for the amylum solution to turn dark blue. ) 12. The sum of reactants used in each experiment may non be precisely the same. There may be an mistake in mensurating or reading the temperatures from the thermometers. As the coloring material alteration of the solution mixture is non a sudden 1. particularly at low temperatures. there may be an mistake in entering the clip of color alteration. Chapter 55Catalysis and industrial procedures Experiment 55. 1Investigating the action of accelerator 1. ( B ) No. 5. ( B ) Time ( s ) 10 20 30 40 50 60 Volume of O2 ( g ) released ( cm3 ) . with the add-on of 0. 5 g MnO2 ( s ) 30 60 85 95 96 96 Time ( s ) 70 80 90 100 110 120 Volume of O2 ( g ) released ( cm3 ) . with the add-on of 0. 5 g MnO2 ( s ) 96 6. ( B ) Time ( s ) 10 20 30 40 50 60 Volume of O2 ( g ) released ( cm3 ) . with the add-on of 1. 5 g MnO2 ( s ) 70 90 95 96 96 Time ( s ) 70 80 90 100 110 120 Volume of O2 ( g ) released ( cm3 ) . with the add-on of 1. 5 g MnO2 ( s ) 8. 9. Manganese ( IV ) oxide MnO2 ( s ) 10. 2H2O2 ( aq ) ? 2H2O ( cubic decimeter ) + O2 ( g ) 11. ( a ) The add-on of manganese ( IV ) oxide greatly increases the rate of decomposition of H peroxide. ( B ) ( I ) The initial rate of reaction is higher. ( two ) The entire clip of reaction is shorter. ( Note: increasing the sum of accelerator would increase the reaction rate. ) ( degree Celsius ) No. 12. Add more H2O2 ( aq ) to the reaction mixture. rapid effervescence shows that manganese ( IV ) oxide has non been used up in the reaction. The catalytic belongings of manganese ( IV ) oxide is still present. Experiment 55. 2Investigating homogenous contact action 5. Mixture ‘y’ . It has a characteristic Sweet odor like certain gums or nail Polish removers. 6. ethyl acetate ; concentrated sulfuric acid 7. CH3COOH ( cubic decimeter ) + CH3CH2OH ( cubic decimeter ) ? CH3COOCH2CH3 ( cubic decimeter ) + H2O ( cubic decimeter ) 8. Homogeneous accelerator. This is because all species are in the same stage in the reaction. i. e. the liquid stage. 9. Sodium carbonate solution reacts with any unreacted ethanoic acid left in the reaction mixture. The strong acetum odor of ethanoic acid is therefore removed. The salt Na acetate formed has no odor. Besides. the ester is indissoluble in H2O and floats on the H2O surface. This makes us easier to observe the odor of ester. Experiment 55. 3Investigating ways to alter the rate of a reaction with a suited accelerator 1. Apparatus: Safety eyeglassess Protective baseball mitts Conic flask ( 100 cm3 ) 5 mensurating cylinders ( 10 cm3 ) Dropper Stopwatch Boiling tubing White tile Chemicals: Ammonium peroxodisulphate solution ( 0. 020 M ) Potassium iodide solution ( 0. 50 M ) Sodium thiosulphate solution ( 0. 010 M ) 0. 2 % amylum solution Iron ( II ) chloride solution ( ~0. 010 M ) Distilled H2O 2. What you will maintain invariable ( Controlled variable ) What you will alter ( Independent variable ) What you will mensurate ( Dependent variable ) volume of ammonium peroxodisulphate solution volume of K iodide solution volume of Na thiosulphate solution sum of 0. 2 % amylum solution with or without utilizing Fe ( II ) solution the clip for the visual aspect of the dark bluish coloring material 3. Figure 1 4. ( 1 ) Using a measurement cylinder. add 10 cm3 of ammonium peroxodisulphate solution to a conelike flask. ( 2 ) Using different mensurating cylinders. add 5 cm3 of K iodide solution. 5 cm3 of Na thiosulphate solution. 1 cm3 of Fe ( II ) chloride solution and 2. 5 cm3 of starch solution to a boiling tubing. ( 3 ) Pour the contents in the boiling tubing into the conelike flask. ( 4 ) Immediately get down the stop watch. ( 5 ) When a dark bluish coloring material of the starch-iodine complex appears in the solution. halt the stop watch. ( 6 ) Record the clip for the visual aspect of the dark bluish coloring material in Table 1. ( 7 ) Repeat stairss ( 1 ) to ( 6 ) . but replace Fe ( II ) chloride solution with 1 cm3 of distilled H2O. 5. Risk appraisal signifier 6. Time for the visual aspect of the dark bluish coloring material With Fe2+ ( aq ) ions ( as a accelerator ) added 59 s Without any accelerator added 3 mins and 52 s Table 1 7. The reaction involves the hit of two negatively charged ions. S2O82? ( aq ) ions and I? ( aq ) ions. which really repel each other. 8. S2O82? ( aq ) + 2Fe2+ ( aq ) ? 2SO42? ( aq ) + 2Fe3+ ( aq ) 2Fe3+ ( aq ) + 2I? ( aq ) ? 2Fe2+ ( aq ) + I2 ( aq ) 9. Mentioning to the two equations in inquiry 8. the S2O82? ( aq ) ions oxidize the Fe2+ ( aq ) ions to Fe3+ ( aq ) ions. At the same clip. the S2O82? ( aq ) ions are reduced to SO42? ( aq ) ions. The Fe3+ ( aq ) ions are strong oxidising agents that oxidize I? ( aq ) ions to I2 ( aq ) . At the same clip. Fe3+ ( aq ) ions are reduced back to Fe2+ ( aq ) ions ( i. e. the accelerator is regenerated ) . Both the equations shown in inquiry 8 involve the hit between positive and negative ions. This will be much more likely to be successful than the hit between two negative ions in the uncatalysed reaction. Therefore. the activation energy of this tract will be lower and the reaction rate will besides be higher. 10. The chemical reaction can be speeded up by the add-on of Fe ( II ) ions. which act as a homogenous accelerator of this reaction. 11. It can be regenerated after the reaction. OR It is specific in action. OR A little sum of accelerator is normally plenty for the catalytic action. 12. Homogeneous accelerator is one which has the same stage as the reactants and merchandises. Sample laboratory study Title: Investigating ways to alter the rate of a reaction with a suited accelerator Aim To plan and transport out an experiment to look into ways to alter the rate of a reaction – by the usage of a suited accelerator. Apparatus and stuffs Safety eyeglassess Protective baseball mitts Conic flask ( 100 cm3 ) 5 mensurating cylinders ( 10 cm3 ) Dropper Stopwatch Boiling tubing White tile Ammonium peroxodisulphate solution ( 0. 020 M ) Potassium iodide solution ( 0. 50 M ) Sodium thiosulphate solution ( 0. 010 M ) 0. 2 % amylum solution Iron ( II ) chloride solution ( ~0. 010 M ) Distilled H2O Chemical reactions involved S2O82? ( aq ) + 2Fe2+ ( aq ) ? 2SO42? ( aq ) + 2Fe3+ ( aq ) 2Fe3+ ( aq ) + 2I? ( aq ) ? 2Fe2+ ( aq ) + I2 ( aq ) Procedure 1. Using a measurement cylinder. 10 cm3 of ammonium peroxodisulphate solution was added to a conelike flask. 2. Using different mensurating cylinders. 5 cm3 of K iodide solution. 5 cm3 of Na thiosulphate solution. 1 cm3 of Fe ( II ) chloride solution and 2. 5 cm3 of starch solution were added to a boiling tubing. 3. The contents in the boiling tubing were poured into the conelike flask. 4. The stop watch was started instantly. 5. When a dark bluish coloring material of the starch-iodine composite appeared in the solution. the stop watch was stopped. 6. The clip for the visual aspect of the dark bluish coloring material was recorded in Table 1. 7. Stairss ( 1 ) to ( 6 ) were repeated. but Fe ( II ) chloride solution was replaced with 1 cm3 of distilled H2O. Consequences Time for the visual aspect of the dark bluish coloring material With Fe2+ ( aq ) ions ( as a accelerator ) added 59 s Without any accelerator added 3 mins and 52 s Table 1 After blending all the chemicals in the conelike flask. the reaction mixture with Fe2+ ( aq ) ions will take a shorter clip for the dark bluish coloring material to look. Analysis 1. In the absence of Fe2+ ( aq ) ions. the reaction between S2O82? ( aq ) ions and I ­Ã‚ ­? ( aq ) ions is slow. As both reactant ions are negatively charged. they tend to drive each other. However. when Fe2+ ( aq ) ions are added. the reaction becomes faster. Fe2+ ( aq ) ions have the same stage ( i. e. aqueous stage ) as the reactants and merchandises. so they are homogenous accelerator of this reaction. 2. Fe2+ ( aq ) ions is a cut downing agent which can cut down S2O82? ( aq ) ions to SO42? ( aq ) ions. The Fe3+ ( aq ) ions formed act as an oxidizing agent. which oxidize I ­Ã‚ ­? ( aq ) ions to I2 ( aq ) ions and renew Fe2+ ( aq ) ions once more. Bing a accelerator. Fe2+ ( aq ) ions are non consumed in the catalytic procedure. Discussion 1. Either Fe2+ ( aq ) ions are Fe3+ ( aq ) ions is a good pick of accelerator for this reaction because the interconversion between Fe2+ and Fe3+ facilitates the reaction between S2O82? ( aq ) ions and I ­Ã‚ ­? ( aq ) ions to happen. 2. The catalytic belongings of Fe2+ ( aq ) ions may be due to the fact that it is easier for the negatively charged S2O82? ( aq ) ions to near the positively charged Fe2+ ( aq ) ions. The same is true when the positively charged Fe3+ ( aq ) ions formed can near the negatively charged I ­Ã‚ ­? ( aq ) ions easier. 3. The experiment is merely a simple trial tubing experiment but the consequence ( color alteration ) is rather obvious and easy to observe. Decision The chemical reaction can be speeded up by the add-on of Fe2+ ( aq ) ions. which act as a homogenous accelerator of this reaction. Answers to inquiries for farther idea 11. It can be regenerated after the reaction. OR It is specific in action. OR A little sum of accelerator is normally plenty for the catalytic action. 12. Homogeneous accelerator is one which has the same stage as the reactants and merchandises. Experiment 55. 4Preparing ethyl alcohol by agitation 3. ( B ) Glucose solution with barm Glucose solution without barm Appearance of the glucose solution a pale brown suspension a clear solution Observations in the limewater clear and colourless clear and colourless 6. ( vitamin D ) Acidified K bichromate solution alterations colour from orange to green. ( degree Fahrenheit ) No coloring material alteration for the acidified K bichromate solution. 7. Glucose solution with barm Glucose solution without barm Appearance of the glucose solution cloudy ; a pale brown suspension clear. no seeable alteration Observations in the limewater milky remains clear and colourless Smell of the glucose solution a odor of intoxicant no characteristic odor 8. accelerator 9. ethyl alcohol ; C dioxide 10. The solution turns milky. It indicates that C dioxide is produced during agitation. 11. In the presence of barm. glucose is converted to ethanol. The presence of ethyl alcohol is indicated by the color alteration of the reaction with acidified K bichromate solution. Ethanol is a cut downing agent. It reduces dichromate ions to chromium ( III ) ions.