Results : Reduction Potentials of Several Redox Couples Galvanic Cell Measured Ecell Anode Equation for Anode Reaction Cathode Equation for Cathode Reaction Cu-Zn +1.19 V Zn Zn → Zn2+ + 2e- Cu Cu2+ + 2e- → Cu Cu-Mg +3.23 V Mg Mg → Mg2+ + 2e- Cu Cu2+ + 2e- → Cu Cu-Fe +0.89 V Fe Fe → Fe2+ + 2e- Cu Cu2+ + 2e- → Cu Zn-Mg +2.00 V Mg Mg → Mg2+ + 2e- Zn Zn2+ + 2e- → Zn Fe-Mg +1.54 V Mg Mg → Mg2+ + 2e Fe Fe2+ + 2e → Fe Zn-Fe +0.29 V Zn Zn → Zn2+ + 2e- Fe Fe2+ + 2e- → Fe Balanced net reaction Cu-Zn Zn (s) + Cu2+ (aq) → Zn2+ (aq) + Cu (s) Cu-Mg Mg (s) + Cu2+ (aq) → Mg2+ (aq) + Cu (s) Cu-Fe Fe (s) + Cu2+ (aq) → Fe2+ (aq) + Cu (s) Zn-Mg Mg (s) + Zn2+ (aq) → Mg2+ (aq) + Zn (s) Fe-Mg Mg (s) + Fe2+ (aq) → Mg2+ (aq) + Fe (s) Zn-Fe Zn (s) + Fe2+ (aq) → Zn2+ (aq) + Fe (s) Zn-Mg = + 2.00 V, Mg-Cu = + 3.23 V The cell potential of Zn-Cu = 3.23 V – 2.00 V = 1.23 V The measured cell potential of Zn-Cu = +1.19 V The value of the sum of the Zn-Mg and Zn-Cu cell potentials are nearly the same as the Cu-Mg cell potential. Zn-Fe = +0.29 V, Zn-Mg = +2.00 V The cell potential of Fe-Mg = 2.00 V – 0.29 V = 1.71 V The measured cell potential of Fe-Mg = +1.54 V The value of the sum of the Zn-Fe and Zn-Mg cell potentials are nearly the same as the Fe-Mg cell potential. Redox Couple Reduction Potential (measured) Reduction Potential (calculated) % Error Cu2+/ Cu +0.4 V +0.310 V 29% Fe2+/ Fe -0.5 V -0.440 V 14% Zn2+/Zn -0.79 V -0.76 V 4% Mg2+/Mg -2.79 V -2.41 V 16% Calculation for Reduction Potential (V) Ecell = Ecathode - Eanode
If the reaction is not spontaneous under standard conditions at 298K, at what temperature (if any) would the reaction become spontaneous? a) 2 PbS (s) + 3 O2 (g) → 2 PbO (s) + 2SO2 (g) ; ΔH° = -844 kJ; ΔS°= -165 J/K b) 2 POCl3 (g) → 2 PCl3 (g) + O2 (g) ; ΔH° = 572 kJ; ΔS°= 179 J/K 5. Consider the reaction H2 (g) + F2 (g) → 2 HF (g). a) Using data in your Appendix B, calculate ΔG° at 25°C b) Calculate ΔG at 298K if the reaction mixture consists of 8.0 bar of H2, 4.5 bar of F2 and 0.36 bar of HF. 6.
|Mass of insulated test tube, spin bar, cyclohexane and |353.25g | | |unknown | | |4. |Mass of unknown |0.15g | A. Warming Curve Data-Pure Cyclohexane |Time |Temp °C |Time |Temp °C |Time |Temp °C |Time |Temp °C | |2.56.30 |6.9 |2.59.30 |6.8 |3.02.30 |6.8 |3.05.30 |7.9 | |2.57.00 |6.9 |3.00.00 |6.9 |3.03.00 |6.9 |3.06.00 |8.2 | |2.57.30 |6.9 |3.00.30 |6.9 |3.03.30 |6.9 |3.06.30 |8.5 | |2.58.00 |6.8 |3.01.00 |6.8 |3.04.00 |7 |3.07.00 |8.9 | |2.58.30 |6.8 |3.01.30 |6.8 |3.04.30 |7.1 |3.07.30 |9.2 | |2.59.00 |6.9 |3.02.00 |6.8 |3.05.00 |7.6 |3.08.00 |9.5 | [pic] 5. Freezing point of pure cyclohexane, from warming Curve is 6.0°C B. Warming Curve Data-Solution Containing Unknown – 941 Trial 1 |Time
This table shows the magnitude found when using the rheostat portion of the experiment. Trial 4 V (v) | I (A) | 2.0 | .02 | 4.0 | .04 | 6.0 | .06 | 8.0 | .08 | 10.0 | 0.1 | 12.0 | 0.12 | 14.0 | 0.14 | 16.0 | 0.16 | 18.0 | 0.18 | 20.0 | 0.20 | Table 4. This table shows the magnitude found when using the Unknown resistor portion of the experiment. In order to find the data from the above tables, my partners and I
pyridinium hydrobromide perbromide type of stationary phase column length column temperature rate flow of the carrier gas List the 4 general factors that affect the separation obtained on a gas chromatograph What specific technique is used to collect/isolate your purified unknown compound at the end of the recrystallization experiment? suction filtration 14 of 22 4/16/12 9:15 PM StudyBlue Flashcard Printing of Lab Final 2211L UGA
The distance between the forces is given by the Coulombs law through the use of the formula F=kq1q2/r2.0.1newtons = 8.99*109*3.2*10-6*7.7*10-7/r2 R= 555.78 Answer to question 3 • Potential difference between the two plates is equal to velocity which is equal to 6.0*106m/s • Force = mass *acceleration = 1.4*10-13*6.0*106 = -8254 nektons The speed of the particles are computed by the formula V=ED. This is equal to 8.5*10-6*0.15. This is equal to 84.1 Answer to question 4 Voltage = current *resistance. This implies that in this case while V is 5.0 and resistance is 1.0*103, current will be equal to 5/1.0*103, = 500 amps B the direction of the conventional current provides the electric charge movement from the positive side of the battery to its negative side as in indicated in the diagram below Answer to question 5 • This section focuses on the equivalent resistance of a circuit. The equivalent resistance will be equal to (5.0*102+1.00*103)2.
10–29 kg. 2. Which one of the following is a fundamental unit in the SI system? A. B. C. D. Ampere Volt Ohm Tesla 3.
PHYSICS - Topic Tracker Version: 2.0 STUDENT NAME: _______________________________ 9.2.4 Space: Special Relativity | Physics HSC Syllabus Dot Points | “Physics 2” Textbook pages: | Additional Tasks orPRACS | “SurfingPhysics”pages: | Completed? sign | Date | 4. Current and emerging understanding about time and space has been dependent upon earlier models of the transmission of light | 4a outline the features of the aether model for the transmission of light | Ch.5 p.68-69 | | #25. p.36-37 | | | | 4b describe and evaluate the Michelson-Morley attempt to measure the relative velocity of the Earth through the aether | Ch.5 p.70 | | | | | | 4c discuss the role of the Michelson-Morley experiments in
Concept Explorations 8.29. Periodic Properties I A hypothetical element, X, has the following ionization energy values: First ionization energy: 900 kJ/mol Second ionization energy: 1750 kJ/mol Third ionization energy: 14,900 kJ/mol Fourth ionization energy: 21,000 kJ/mol Another element, Y, has the following ionization energy values: First ionization energy: 1200 kJ/mol Second ionization energy: 2500 kJ/mol Third ionization energy: 19,900 kJ/mol Fourth ionization energy: 26,000 kJ/mol * a. To what family of the periodic table would element X be most likely to belong? Explain? * X belongs to Group 2 of the periodic table because it has a low first and second ionization energy, however, a higher second and third.
For developing countries, the overall' projected potential was estimated at 400x1018 joule for geothermal energy with the projected capacity in 1990. Efforts are being made to use this energy for generating power and creating refrigeration. Geothermal energy can either be used to produce electricity in power station or can be used directly as primary heat. Advantages: The green house gas emissions of geothermal stations are much less than that of coal burning power stations. In Ohaake in New Zealand about 320 gm of C02 is produced for each KW hour of electricity produced against 950 to 960 gm.