The formation of molecular hydrogen at 3000 K proceeds through the following elementary reaction: 2H (g)...

   

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The formation of molecular hydrogen at 3000 °K proceeds through the following elementary reaction: 2H (g) + Ar (9) H2(g) + Ar (9) k = 2.2 × 108 mol-2.12.s-1 k, 2.2 x 10 mol-1.L.s-1 Write the rate law for this process with respect to H2. (a) Calculate the rate of the reverse reaction (r=-d[H2(g)]/dt) given [H2(g)] = 4.1×103 mol·L¹ and [Ar(g)] = 4.1×10+ mol·L¹; (b) What concentration of Ar is needed to double the reverse reaction rate computed in (a); (c) Calculate the concentration of [H(g)] needed for the forward reaction rate (r=d[H2(g)]/dt) to be equal to the reverse reaction rate computed under the process conditions given in (a). 2) [20] The decomposition of dinitrogen pentoxide at low temperatures results in the formation of a brown-colored gas with the chemical formula N2O4, known as dinitrogen tetroxide, a harmful pollutant found in the air together with nitrogen dioxide. On the basis of the chemical equation 2N205(g) → 2N204(g) + O2(g) a student assumed that the reaction would be second order. Using the following data, determine whether or not the student's assumption is correct. t/s 0 1200 2400 3600 4800 6000 7200 8400 9600 10800 12000 13000 P(N:Os)/(torr) 268.7 247.2 236.2 227.1 217.8 209.5 201.8 193.2 185.8 178.1 164.9 152.4 3) [10] A piston-cylinder system is used to store 1000 J of work by keeping an ideal gas compressed at a pressure of 4 atm. The stored energy is to be released to the surroundings by allowing the piston to expand isothermally at 25°C to a lower pressure of 1.5 atm. Calculate the amount of gas necessary to carry out the energy transfer if the external pressure is 1 atm. 4) [20] Sulfur oxides are pollutants that contribute to the formation of acid rain, as well as particulate pollution. Use the data on the free energy of formation of the oxides of sulfur provided in the table below to determine at what temperature is the formation of SO2(g) and SO3(g) equally thermodynamically favorable? Above what temperature is the S2O(g) the preferred product of the rection of S with O2? Over what temperature range is SO2(g) the preferred product? At high temperatures, will SO2(g) be stable? AG so [kJ/mol] AGs₂o [kJ/mol] T[°K] 0 5.028 -58.859 500 -37.391 - 122.290 AG so₂ [kJ/mol] -294.299 AG so,[kJ/mol] -390.025 -300.871 - 352.668 1000 - 64.382 - 179.508 1500 - 66.854 -217.275 -288.725 -252.239 2000 - 69.294 - 258.325 - 215.929 2500 - 71.708 -301.726 - 179.675 -293.639 -211.247 - 129.768 - 48.855 3000 - 74.111 -346.922 -143.383 31.748 3500 - 76.512 -393.557 - 106.996 112.210 4000 - 78.908 -441.382 -70.484 192.643 4500 -81.291 -490.215 -33.829 273.120 5000 - 83.648 -539.913 2.9821 353.700 5500 - 85.965 -590.360 39.960 434.427 6000 - 88.235 -641.455 77.128 515.359 5) [20] An industrial process generates a waste stream of concentrated sulfuric acid which is neutralized by hydrated lime according to the following highly exothermic reaction to produce gypsum and water Ca(OH) 2 (s) + H2SO4(9) CaSO4(s) + H2O(1) Determine the amount of heat generated when I mole of lime is mixed with 1 mole of waste sulfuric acid in a closed chemical vessel that is immersed in a 2-liter water bath apparatus. If all the heat released during the neutralization reaction is absorbed by the water in the bath apparatus estimate the final temperature of the water. Assume that heat losses are negligible during the energy transfer process and that the initial water temperature was 25°C at 1 atm. The formation of molecular hydrogen at 3000 °K proceeds through the following elementary reaction: 2H (g) + Ar (9) H2(g) + Ar (9) k = 2.2 × 108 mol-2.12.s-1 k, 2.2 x 10 mol-1.L.s-1 Write the rate law for this process with respect to H2. (a) Calculate the rate of the reverse reaction (r=-d[H2(g)]/dt) given [H2(g)] = 4.1×103 mol·L¹ and [Ar(g)] = 4.1×10+ mol·L¹; (b) What concentration of Ar is needed to double the reverse reaction rate computed in (a); (c) Calculate the concentration of [H(g)] needed for the forward reaction rate (r=d[H2(g)]/dt) to be equal to the reverse reaction rate computed under the process conditions given in (a). 2) [20] The decomposition of dinitrogen pentoxide at low temperatures results in the formation of a brown-colored gas with the chemical formula N2O4, known as dinitrogen tetroxide, a harmful pollutant found in the air together with nitrogen dioxide. On the basis of the chemical equation 2N205(g) → 2N204(g) + O2(g) a student assumed that the reaction would be second order. Using the following data, determine whether or not the student's assumption is correct. t/s 0 1200 2400 3600 4800 6000 7200 8400 9600 10800 12000 13000 P(N:Os)/(torr) 268.7 247.2 236.2 227.1 217.8 209.5 201.8 193.2 185.8 178.1 164.9 152.4 3) [10] A piston-cylinder system is used to store 1000 J of work by keeping an ideal gas compressed at a pressure of 4 atm. The stored energy is to be released to the surroundings by allowing the piston to expand isothermally at 25°C to a lower pressure of 1.5 atm. Calculate the amount of gas necessary to carry out the energy transfer if the external pressure is 1 atm. 4) [20] Sulfur oxides are pollutants that contribute to the formation of acid rain, as well as particulate pollution. Use the data on the free energy of formation of the oxides of sulfur provided in the table below to determine at what temperature is the formation of SO2(g) and SO3(g) equally thermodynamically favorable? Above what temperature is the S2O(g) the preferred product of the rection of S with O2? Over what temperature range is SO2(g) the preferred product? At high temperatures, will SO2(g) be stable? AG so [kJ/mol] AGs₂o [kJ/mol] T[°K] 0 5.028 -58.859 500 -37.391 - 122.290 AG so₂ [kJ/mol] -294.299 AG so,[kJ/mol] -390.025 -300.871 - 352.668 1000 - 64.382 - 179.508 1500 - 66.854 -217.275 -288.725 -252.239 2000 - 69.294 - 258.325 - 215.929 2500 - 71.708 -301.726 - 179.675 -293.639 -211.247 - 129.768 - 48.855 3000 - 74.111 -346.922 -143.383 31.748 3500 - 76.512 -393.557 - 106.996 112.210 4000 - 78.908 -441.382 -70.484 192.643 4500 -81.291 -490.215 -33.829 273.120 5000 - 83.648 -539.913 2.9821 353.700 5500 - 85.965 -590.360 39.960 434.427 6000 - 88.235 -641.455 77.128 515.359 5) [20] An industrial process generates a waste stream of concentrated sulfuric acid which is neutralized by hydrated lime according to the following highly exothermic reaction to produce gypsum and water Ca(OH) 2 (s) + H2SO4(9) CaSO4(s) + H2O(1) Determine the amount of heat generated when I mole of lime is mixed with 1 mole of waste sulfuric acid in a closed chemical vessel that is immersed in a 2-liter water bath apparatus. If all the heat released during the neutralization reaction is absorbed by the water in the bath apparatus estimate the final temperature of the water. Assume that heat losses are negligible during the energy transfer process and that the initial water temperature was 25°C at 1 atm.