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Hire A Tutor For Your Homework www.helpingtutors.com Alternatevely contact me for it's solution at flat rate of $20 licservernoida@gmail.complease answers must be…
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Hire A Tutor For Your Homework www.helpingtutors.com Alternatevely contact me for it's solution at flat rate of $20 licservernoida@gmail.complease answers must be done in the attached questions. Thanks 1) Part A How much work is done when a 195 g tomato is lifted 15.9 m ? Express your answer with the appropriate units. 2) Part A - Describing and Calculating Energy Changes Which of the following objects has the greatest kinetic energy? Which of the following objects has the greatest kinetic energy? a 500-kg motorcycle moving at 100 km/h a 1,000-kg car moving at 50 km/h a 1,500-kg car moving at 30 km/h a 5,000-kg truck moving at 10 km/h a 10,000-kg truck moving at 5 km/h 3) At 20 ∘C (approximately room temperature) the average velocity of N2 molecules in air is 1050 mph. Part A What is the average speed in m/s? Express your answer using four significant figures. Part B What is the kinetic energy (in J) of an N2 molecule moving at this speed? Express your answer using four significant figures. Part C What is the total kinetic energy of 1 mol of N2 molecules moving at this speed? Express your answer using four significant figures. 4) Part A - Relating Heat and Work to Changes of Internal Energy Consider the following four cases i. A chemical process in which heat is absorbed. ii. A change in which q=30 J, w=44 J. iii. A process in which a system does work on its surroundings with no change in q. iv. A process in which work is done on a system and an equal amount of heat is withdrawn. In how many of these cases does the internal energy of the system decrease? Consider the following four cases i. A chemical process in which heat is absorbed. ii. A change in which , . iii. A process in which a system does work on its surroundings with no change in . iv. A process in which work is done on a system and an equal amount of heat is withdrawn. In how many of these cases does the internal energy of the system decrease? 0 1 2 3 4 5) Part AA piston has an external pressure of 15.0 atm. How much work has been done in joules if the cylinder goes from a volume of 0.120 liters to 0.470 liters? Express your answer with the appropriate units. 6) Part A If a balloon is expanded from 0.055 L to 1.403 L against an external pressure of 1.02 atm, how many L⋅atm of work is done? If a balloon is expanded from 0.055 to 1.403 against an external pressure of 1.02 , how many of work is done? -0.056 L⋅atm -1.37 L⋅atm 1.43 L⋅atm 1.49 L⋅atm 1.39 L⋅atm 7) A gas is confined to a cylinder under constant atmospheric pressure, as illustrated in the following figure. When 0.440 kJ of heat is added to the gas, it expands and does 215 J of work on the surroundings. Part A What is the value of ΔH for this process? Express the energy in kilojoules to three significant digits. Part B What is the value of ΔE for this process? Express the energy in kilojoules to three decimal places. 8) Part A - Relating ΔH to Quantities of Reactants and Products The complete combustion of ethanol, C2H5OH (FW = 46.0 g/mol), proceeds as follows: C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l) ΔH = −555 kJ What is the enthalpy change for combustion of 15.0 g of ethanol? The complete combustion of ethanol, (FW = 46.0 ), proceeds as follows: What is the enthalpy change for combustion of 15.0 of ethanol? -12.1 kJ -181 kJ -422 kJ -555 kJ -1700 kJ 9) Part A A total of 2.00 mol of a compound is allowed to react with water in a foam coffee cup and the reaction produces 155 g of solution. The reaction caused the temperature of the solution to rise from 21.00 to 24.70 ∘C. What is the enthalpy of this reaction? Assume that no heat is lost to the surroundings or to the coffee cup itself and that the specific heat of the solution is the same as that of pure water. Enter your answer in kilojoules per mole of compound to three significant figures. 10) Part A - Measuring ΔH Using a Coffee-Cup Calorimeter When 0.243 g of Mg metal is combined with enough HCl to make 100 mL of solution in a constantpressure calorimeter, the following reaction occurs: Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g) If the temperature of the solution increases from 23.0 ∘C to 34.1 ∘C as a result of this reaction, calculate ΔH in kJ/mol of Mg. Assume that the solution has a specific heat of 4.18 J/g∘C. When 0.243 of metal is combined with enough to make 100 of solution in a constant-pressure calorimeter, the following reaction occurs: If the temperature of the solution increases from 23.0 to 34.1 as a result of this reaction, calculate in of . Assume that the solution has a specific heat of 4.18 . −19.1 kJ/m ol −111 kJ/mo l −191 kJ/mol −464 kJ/mo l −961 kJ/mo l 11) Part A - Measuring qrxn Using a Bomb Calorimeter The combustion of exactly 1.000 g of benzoic acid in a bomb calorimeter releases 26.38 kJ of heat. If the combustion of 0.550 g of benzoic acid causes the temperature of the calorimeter to increase from 22.01∘C to 24.27∘C, calculate the heat capacity of the calorimeter. The combustion of exactly 1.000 of benzoic acid in a bomb calorimeter releases 26.38 of heat. If the combustion of 0.550 of benzoic acid causes the temperature of the calorimeter to increase from 22.01 to 24.27, calculate the heat capacity of the calorimeter. 0.660 kJ/∘ C 6.42 kJ/∘C 14.5 kJ/∘C 21.2 kJ/∘C 32.7 kJ/∘C 12) When a 6.50-g sample of solid sodium hydroxide dissolves in 100.0 g of water in a coffee-cup calorimeter (the following Figure), the temperature rises from 21.6 ∘C to 37.8 ∘C. Part A Calculate ΔH (in kJ/mol NaOH) for the solution process NaOH(s)→Na+(aq)+OH−(aq) Assume that the specific heat of the solution is the same as that of pure water. Express your answer with the appropriate units. 13) Part A - Using Hess’s Law to Calculate ΔH Calculate ΔH for 2 NO(g) + O2(g) → N2O4(g) using the following information: N2O4(g)2 NO(g) + O2(g)→→2 NO2(g)2 NO2(g)ΔHΔH==+57.9 kJ−114.1 kJ Calculate for using the following information: 2.7 kJ -55.2 kJ -85.5 kJ -171.0 kJ +55.2 kJ 14) Part A From the enthalpies of reaction 2C(s)+O2(g)→2CO(g)ΔH=−221.0kJ 2C(s)+O2(g)+4H2(g)→2CH3OH(g)ΔH=−402.4kJ calculate ΔH for the reaction CO(g)+2H2(g)→CH3OH(g) Express your answer with the appropriate units. 15) The standard heat of formation, ΔH∘f, is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have ΔH∘f=0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Consider, for example, the reaction 2NO(g)+O2(g)⇌2NO2(g) with heat of formation values given by the following table: ΔH∘f Substanc e (kJ/mo l) NO(g) 90.2 O2(g) 0 NO2(g) 33.2 Then the standard heat of reaction for the overall reaction is ΔH∘rxn===ΔH∘f(products)2(33.2)−114 kJ−−ΔH∘f(reactants)[2(90.2)+0] Part A For which of the following reactions is ΔH∘rxn equal to ΔH∘f of the product(s)? You do not need to look up any values to answer this question.Check all that apply. Check all that apply. CO(g) +12O2(g)→CO2(g) BaCO3(s)→BaO(s) +CO2(g) Li(s)+12F2(g)→LiF(s) 2Li(s)+F2(g)→2LiF(s) Li(s)+12F2(l)→LiF(s) C(s,graphite) +O2(g)→CO2(g) Part B The combustion of pentane, C5H12, occurs via the reaction C5H12(g)+8O2(g)→5CO2(g)+6H2O(g) with heat of formation values given by the following table: ΔH∘f Substanc (kJ/mol e ) C5H12 (g ) -119.9 CO2(g) −393.5 H2O(g) −241.8 Calculate the enthalpy for the combustion of 1 mole of pentane. Express your answer to four significant figures and include the appropriate units 16) Part A - Equations Associated with Enthalpies of Formation If the heat of formation of H2O(l) is -286 kJ/mol, which of the following thermochemical equations for the formation of H2O is correct? If the heat of formation of is -286 , which of the following thermochemical equations for the formation of is correct? 2 H2(g) + O2(g) → 2 H2O(l) ΔH= −286 kJ H2O(l) → H2(g) + 86 kJ 12 O2(g) ΔH=2 H2(g) + O(g) → H2O(g) 286 kJ ΔH=− 2 H(g) + O(g) → H2O(l) −286 kJ ΔH= H2(g) + 286 kJ 12 O2(g) → H2O(l) ΔH=− 17) Calcium carbide (CaC2) reacts with water to form acetylene (C2H2) and Ca(OH)2. Part A From the following enthalpy of reaction data and data in Appendix C, calculate ΔH∘f for CaC2(s): CaC2(s)+2H2O(l)→Ca(OH)2(s)+C2H2(g)ΔH∘=−127.2kJ 18) Alexander, who weighs 168 lb , decides to climb Mt. Krumpett, which is 5640 m high. For his food supply, he decides to take nutrition bars. The label on the bars states that each 100- g bar contains 10g of fat, 40 g of protein, and 50 g of carbohydrates. One gram of fat contains 9 Calories, whereas each gram of protein and carbohydrates contains 4 Calories. Nutrition facts Calories per gram Fat 9 Protein 4 Carbohydrates 4 Part A Alexander wants to know exactly how many bars to pack in his backpack for the journey. To provide a margin of safety, he assumes that he will need as much energy for the return trip as for the uphill climb. How many bars should Alexander pack? Enter the exact answer to two significant figures. Do not round to an integer. 19) Part A - Estimating the Fuel Value of a Food from Its Composition A stalk of celery has a caloric content (fuel value) of 9.0 kcal. If 1.0 kcal is provided by fat and there is very little protein, estimate the number of grams of carbohydrate and fat in the celery.A stalk of celery has a caloric content (fuel value) of 9.0 . If 1.0 is provided by fat and there is very little protein, estimate the number of grams of carbohydrate and fat in the celery. 1 g carbohydrate and 2 g of fat 2 g carbohydrate and 1 g fat 2.2 g carbohydrate and 0.1 g fat 32 g carbohydrate and 10 g fat 2 g carbohydrate and 0.1 g fatHire A Tutor For Your Homework www.helpingtutors.com Alternatevely contact me for it's solution at flat rate of $20 licservernoida@gmail.com
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