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Chlorinated solvents such as carbon tetrachloride (CCl4) can be degraded in a process called reductive dechlorination where Cl atoms are removed and replaced with H atoms. For example: CCl4 + H+ +2e¯ ⇒ CHCl3 + Cl- Eº-0.67 V In the process of in situ bioremediation an electron donor such as acetate (CH3COO-) is typically added and is oxidized to provide the electrons for the reduction of CCI4. In groundwater devoid of oxygen, nitrate typically serves as the electron acceptor. Answer the questions below using data from Appendix A and that provided above. i) Is it possible that CCl4 could serve as an electron acceptor for acetate? ii) Which electron acceptor, CCl4 or NO3, would be thermodynamically preferred? iii) What do the results in i and ii imply for remediation in an aquifer containing nitrate? (provide a qualitative answer)

- 144 / Natural Sciences / Chemistry And Polymer Science / Chemie zzes / Oplossingsewewig | Solubility Equilibria A solution contains 0.002 M Ag* and 1.6 x 105 M Zn2*, and the ions need to be separated. For this purpose co- is added to the solution so that both Ag,CO3 (Ksp = 8.1 x 10-12) and ZnCO3 (Ksp = 1.0 x 10-10) can precipitate from the solution. What will the concentration of co; be just before the first salt starts to precipitate. (Please give your answer with 2 significant figures.) Answer Check

Calculate the solubility at 25 °C of PbCO, in pure water and in a 0.0040M Pb(NO3)2 solution. You'll find Kp data in the ALEKS Data tab. Round both of your answers to 2 significant digits. solubility in pure water: solubility in 0.0040 M Pb(NO3)2 solution: -7 g 3.2 x 10 Do L -11 g 2.5 x 10 L X × G 号

1. Calculate AH for the reaction: Use the following data: N₂ + O₂2NO 2NO N₂ + 0₂ 2NO+ O₂ → 2NO₂ Unit 7 - Worksheet 4: Hess's Law 2. Calculate AH for the reaction: Use the following data: required! C(graphite) + O₂ → CO₂ C(diamond) + O₂ → CO₂ Use the following data: 3. Calculate AH for the reaction: 2 Al + 1/2O₂ → Al2O3 N₂ + 20₂ >> 2NO₂ 2 Fe + 1½ 0₂ → Fe₂O3 C(graphite) → C (diamond) 2 Al + Fe₂O3 →2Fe + Bat Name: 00 AH = +180 kJ AH=-180kJ 012 Al₂O3 ΔΗ = - 112 kJ AH = - 394 kJ AH = -395 kJ AH = -1669 kJ AH = -824 kJ

Consider the calcination of CaCO3: CaCO3 -> CaQ + CO, Before calcination, the initial weight of CaCO3 is 2.5g. After calcination, the final weight of CaCO3 was measured at 2.0 g. Calculate the conversion of CaCO; particles (x) using the following equation: m CaCO, -m CaCo, ) x = m Caco, -MCao |

12:06 A * A * ll 68%i Zoom v Leave • REC Breakout Rooms GROUP WORK An iron ore was analyzed by dissolving a 1.1324 g sample in concentrated HCI. The resulting solution was diluted with water and the iron (III) was precipitated as the hydrous oxide Fe,O3.xH,O by the addition of NH3. After filtration and washing, the residue was ignited at a high temperature to give 0.5394 g of pure Fe,03 (159.69g/mol). Calculate (a) % Fe (55.847g/mol) and (b) % Fe,04(231.54g/mol) in the sample. •. 28 Unmute Start Video Share Participants More II

5. Calculate Art and Ar So for the autotonization of water H20 cl) → Hcaq) + OH (aq) T(K) Kw 273 1.14*10-15 298 1.00 x 10-14 308 2.09 x 1014 313 2.92X10714 323 5.47 x 10-14 Use a spreadsheet to create the graph required to solve this problem.

(a) (c) HO OH 1. BH3 2. H₂O₂, NaOH 3. PCC 4. CH3MgBr 5. H3O+ workup Na₂Cr₂O7 H₂SO4, H₂O

Calculate the solubility at 25 °C of PbCO3 in pure water and in a 0.0120M Pb(NO3), solution. You'll find Kp data in the ALEKS Data tab. sp Round both of your answers to 2 significant digits. solubility in pure water: solubility in 0.0120 M Pb(NO3)2 solution: 170 170 ☐x10 X 0x0 00

Ca(OH)2(aq) + 2HCl(aq) → CaCl2(8) + 2H2O(1) 2. Standar... 1req For the reaction 3. AS surrou... 1req 4. AG° = A... 1req 5. AG: Pre... 1req 6. AG: Enthal... M 7. AG fro... 1req 8. Calculat... 1req 9. Calculat... 1req Question Question Question 10. Calcul... 1req AH° 30.2 kJ and AS° = 206 J/K The equilibrium constant for this reaction at 280.0 K is Assume that AH° and As are independent of temperature. Submit Answer Retry Entire Group 3 more group attempts remaining

11:17 Today Edit 11:09 AM .) Balance the following: CH12O6{s) + O:lg) > Co:(g) H;0O(g) A) Balance and then write the total ionic and the net ionic equation for the following. Correct physicarstates must be included. NOTE: All reactions are in water a. Strontium acetate + hydrobromic acid Molecular Total lonic Net-ionic b. Lithium hydroxide + plumbous acetate Molecular Total lonic Net-ionic c. Mercury (1) nitrate + cesium carbonate Molecular Total lonic Net-ionic

Given the data in the table below, AHrxn for the reaction Ca(OH); + 2H;AsO4 → Ca(H;AsO4)2 + 2H;O is _ kJ. [A] -4219 (B] -130.4 [C] -4519 [D] -76.4 AH, (kJ/mol) -986.6|| Substance Ca(ОН), HASO, Ca(H;AsOa)2 -900.4 -2346.0 H;0 -285.9 O A В C D

Calculate the COD (gr COD/gr substrate) for (show how you balance the redox reactions): a) Glycerol (C3H8O3) b) Methanol (CH3OH)

A political candidate fighting for a smoke-free environment conducts an experiment in a room containing 1400 cubic feet of air that is initially free of carbon monoxide. Beginning at time t=0, cigarette smoke containing 4% carbon monoxide is introduced into the room at the rate of 0.1 cubic foot perminute, and the well-circulated mixture is allowed to leave the room at the same rate. If carbon monoxide levels in the air reach 0.012%, it is harmful to the human body. Find the time at which this unhealthy level is reached.

2 When 50 cm' of hydrochloric acid of concentration 2.0 mol dm is added to 50 cm' of sodium hydroxide solution of concentration 2.0mol dm, the temperature increase is 13.0°C HCl(aq) + NAOH(aq) + NaCl(aq) + H,O(1) The experiment is repeated using 25 cm of the same hydrochloric acid and 50 cm' of the same sodium hydroxide solution. What is the temperature increase? O A 4.9°C I B 6.5°C I C 8.7°C D 13.0°C

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b) Determine the standard enthalpy change and std. Gibbs free energy change of reaction at 400 k for the reaction Co(g) +2H2(g) → CH;OH (g) At 298.15 K, AH?.co )= -26.41 kcal/mol, AH?.CH,OH()= -48.08 kcal/mol, AG.co )= -32.8079 kcal/mol, AG.CH,OH(@)= -38.69 kcal/mol, The standard heat capacity of various components is given by. CS = a + bT + cT2 + dT³, where C is in cal/mol-K and T is in K |Component b x10 e x105 d x10° a -0.291 CH3OH CO 4.55 2.186 -1.92 6.726 0.04 0.1283 -0.5307 H2 6.952 -0.0457 0.09563 -0.2079

Extensions Help kt 10 Calibri 6 1 4 1.3 Y 2 f7 12 + BIUA 7. Scrubbers are a type of pollution control technology installed on industry smokestacks to capture sulfur dioxide before it is emitted to the atmosphere. Once collected, the sulfur dioxide can be used to manufacture sulfuric acid, which can be sold to other companies that make &7 U 3 1 10. Why is it essential to continually monitor air and water quality? detergents. Explain how the use of scrubber technology benefits both industry and the environment. 8 8. Most North American automobile manufacturers are shifting their production from gasoline powered vehicles to electric vehicles. What effect should this trend have on acid rain? 4 fg Explain how the concentration of a pollutant is related to the severity of its impact on the environment. Lesson 7: Remediate Chemical Pollution f10 5 hp insert 9 E ▼ EYE- f11 6 O f12 mismatisla THEOLOG prt scr 7 G BRUCK 63°F Cloudy delete backspace E

Consider the following equilibrium reaction: Baz(PO4), (s) = 3 Ba2*(aq) + 2 PO,3-(aq) Kc = 3.4 x 10-3 %D 2.00 moles of each reactant and product were placed in 5.00 L of water, mixed and allowed to reach equilibrium. a) Write the Qc expression (LMA) for this reaction. b) Calculate the value of Qc. (Show all work for full credit.) c) In which direction will this reaction proceed to establish equilibrium. Explain your answer. d) Once equilibrium is reached, it was found that the barium ions CHANGED by 0.455 mol. How many moles of each reactant and product are present at equilibrium? (BOX YOUR FINAL ANSWER.)

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Methanogenic bacteria convert acetic acid (CH3COOH) to CO2{g) and CH4(g). AH?, (k/mol) AG°;, (kJ/mol) CH3COOH -484.5 |-389.9 |-393.5 |-394.4 CHA(g) |-50.8 -74.8 1st attempt Part 2 Calculate AG°r rxn- AG°, kJ rxn

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