March 17, 2013
Name : Ryan annasdass arokiasamy
ID : 1206875
Group Members : Chan Pei Qie,Chong Ven Yen
Name : Ryan annasdass arokiasamy
ID : 1206875
Group Members : Chan Pei Qie,Chong Ven Yen experiment 19 kinetics : the study of a chemical reaction experiment 19 kinetics : the study of a chemical reaction
Results
Part A [I-] / mol dm-3 | [S2O82-] / mol dm-3 | [S2O32-] / mol dm-3 | Time /s | Rate of I2 formation / mol dm-3 s-1 | 0.2 | 0.2 | 0.01 | 1.25 | 0.1600 | 0.2 | 0.15 | 0.01 | 13.37 | 0.0150 | 0.2 | 0.10 | 0.01 | 26.00 | 0.0077 | 0.2 | 0.05 | 0.01 | 66.25 | 0.00075 |
Part B [I-] / mol dm-3 | [S2O82-] / mol dm-3 | [S2O32-] / mol dm-3 | Time /s | Rate of I2 formation / mol dm-3 | 0.2 | 0.2 | 0.01 | 3.45 | 0.0580 | 0.15 | 0.2 | 0.01 | 7.56 | 0.0198 | 0.10 | 0.2 | 0.01 | 9.06 | 0.0110 | 0.05 | 0.2 | 0.01 | 23.91 | 0.0021 |
Part C Initial temperature/ OC | Final temperature/ OC | Time t /s | Rate of I2 formation / mol dm-3 | 1/T (1/K) | Log t | 15 | 21 | 29 | 0.00690 | 0.003472 | 1.462 | 24 | 25 | 20 | 0.01000 | 0.003367 | 1.301 | 35 | 42 | 13 | 0.01538 | 0.003247 | 1.114 | 45 | 40 | 8 | 0.02500 | 0.003145 | 0.903 |
Calculations & Questions
The effect of temperature is that it increases the rate of reaction, observed here by the higher temperatures giving a much faster reaction time a) Is reaction (2) fast or slow with respect to reaction (1)? Explain your reasoning or record any test you do to help reach your conclusion
Reaction (2) is fast with respect to reaction (1).
Reaction (2): I2+2 S2O32-→ 2 I-+ S4O62- occurs extremely fast, I2 formed in the reaction is consumed immediately and when the limiting agent S2O32- is used up, I2 reacts with the starch indicator to form a blue color solution.
b) Does reaction (1) or (2) control the time required for the blue colour to appear?
Reaction (1): 2I-+ S2O82-→I2+2SO42- controls the time required for the blue colour to
References: Martin S. Silberberg, Chemistry the Molecular Nature of Matter and Change, Fifth Edition, McGraw Hill, 2005. F. Albert Cotton, Geoffrey Wilkinson, Carlos A. Murillo, and Manfred Bochmann, Advanced Inorganic Chemistry, Sixth edition, John Wiley& Son.1999. F. Albert Cotton, Geoffrey Wilkinson, Paul L. Gaus, Basic Inorganic Chemistry, Third Edition, John Wiley& Son.1995. John C. Kotz, Paul M. Treichel, and Gabriela C. Weaver, Chemistry and Chemical Reactivity, Sixth Edition, Thomson 2006.