Include the sign of the, Using standard heats of formation, calculate the standard enthalpy change for the following reaction. From the following enthalpy of reaction data and data in Appendix C, calculate Hf for CaC2(s): CaC2(s)+2H2O(l)Ca(OH)2(s)+C2H2(g)H=127.2kJ, CaC2(s) + 2 H2O(l) Ca(OH)2(s) + C2H2 (g) = 127.2kJ. As an example, the British and German standards for the content of the coarser fractions are 295 L/kg and 300 L/kg respectively (at 101 kPa pressure and 20 C (68 F) temperature). Using standard heats of formation, calculate the standard enthalpy change for the following reaction. 2Na(s) + 2H_2O (l) to 2NaOH (aq) + H_2 (g), Using standard heats of formation, calculate the standard enthalpy change for the following reaction. sachant qu' ce moment, il avait 12 ans en quelle anne armnius est-il n? which is the equation in the previous section for the enthalpy of combustion PLEASE HELP!!! C*t3/3 + D*t4/4 E/t + F H 2Al (s) + 3/2 O_2 (g) to Al. All rights reserved. It is also known as calcium acetylide, phenyl glyceryl ether diacetate, and glycerol phenyl ether diacetate. The presence of flammable gases in coal mines led to miner safety lamps such as the Davy lamp, in which a wire gauze reduces the risk of methane ignition. (a) C_2H_4(g)+ 30_2(g) --> 2C0_2(g) + 2H_20(l) kJ/mol (b) 2H_2S (g) + 3 O_2 (g) --> 2, Calculate the standard reaction enthalpy for: CaCO_3 (s) + 2HCl (aq) \rightarrow CaCl_2 (aq) + H_2O + CO_2 (g) \\ \Delta H_f^{\circ} (H_2O(phi)) = -285.83 kJ/mol \\ \Delta H_f^{\circ} (CO_2(g)) =, Using standard heats of formation, calculate the standard enthalpy change for the following reaction. I need help to compute this question: Standard molar enthalpy of formation of NH3 is -45.9 Kj/mol. The value of the enthalpy of formation can be used to determine the total enthalpy change . [25] When it comes into contact with water, the gas produced drives moles away.[26]. Reaction 1: NaOH + HCl, Reaction 2: NaOH + NH4Cl, and Reaction 3: HCl + NH3. The standard enthalpy of formation is then determined using Hess's law. Such as in the song Jimmy by M.I.A look at aaja in the dictionary My indian boyfriend told me is meaning come to me, 6 Answers I have never had or heard of that particular brand, but have had several here in Canada, plus a number in the Caribbean and Asia, and there all the same, small cut hot dogs in a can, no need q now please.. Name the major nerves that serve the following body areas:? The Standard enthalpy of formation of gaseous H2O at 298K is -241.82 kJ mol-1. This has been going on for about a week Every time I try to watch a video on Youtube from my laptop I get instantly redirected to "gslbeacon.ligit.com." 4 In the Netherlands calcium carbide is used around new-year to shoot with milk churns.[22]. O Water dripping on the carbide creates acetylene gas, which burns and emits light. CaO(s) + CO2(g) to CaCO3(s), Use standard enthalpies of formation to calculate delta H_rxn for the following reaction. CaO(s) + 3 C(s) CaC2(s) + CO(g) . References Formula 6 Answers They say Kali Ma Theyre referencing this scene from the movie Indiana Jones and the Temple of Doom: Calcium Carbide (CaC2) reacts with water to form acetylene (C2H2) and Ca(OH)2. The hydrolysis reaction of Al4C3 can be written as Al4C3+12H2O3CH4+4Al(OH)3. . CaO (s)+3C (s)CaC 2 (s)+CO (g) CaO (s)+3C (s)CaC2 (s)+CO (g) H=464.8kJ H=464.8kJ The value of Can I use this word like this: The addressal by the C.E.O. CO(g) + 3H2(g)CH4(g) + H2O(g) ? In the early days, it was used as headlights for automobiles. 26. In carbide lamps, calcium carbide plays an integral role. I_{2}(g)+Cl_{2}\rightarrow 2ICl(g) ({Blank}) KJ, Given the standard enthalpy changes for the following two reactions: N 2 ( g ) + 2 O 2 ( g ) N 2 O 4 ( g ) , H = 9.2 k J 2 N 2 O ( g ) 2 N 2 ( g ) + O 2 ( g ) , H = 164.2 k J , what is the standard enthalpy change for the reaction 2 N 2 O, Given the standard enthalpy changes for the following two reactions 4 C ( s ) + 5 H 2 ( g ) C 4 H 10 ( g ) , H = 125.6 k J C 2 H 4 ( g ) 2 C ( s ) + 2 H 2 ( g ) , H = 52.3 k J , what is the standard enthalpy change for the reaction 2 C. Using standard enthalpies of formation, what is the standard enthalpy of reaction (delta Hrxn^o)? CaCN3 3. What is the enthalpy change of 5.38g N2 and 3.32g H2 react to produce NH3? Calcium Carbide in its pure form appears as a colourless crystalline solid and is a rock-like structure at room temperature. Calcium carbide (CaC2) reacts with water to form acetylene (C2H2) and Ca(OH)2. The standard enthalpy change of any reaction can be calculated from the standard enthalpies of formation of reactants and products using Hess's law. CaC2 is a chemical compound with a chemical name Calcium Carbide. en - 646 avant jsus christ , les deux volcans ont t en ruption. There are three reactions. Estimate its value at 100 C given the following values of the molar heat capacities at constant pressure: H2O (g): 33.58 JK-1mol-1, H2 (g): 28.84 JK-1mol-1, O2 (g): 29.37 JK-1mol-1. Calcium carbide is also used in the desulphirisation of iron. The standard pressure value p = 105 Pa (= 100 kPa = 1 bar) is recommended by IUPAC, although prior to 1982 the value 1.00 atm (101.325 kPa) was used. It is used in bamboo cannons as well as big-bang cannons. . The common crystalline form at room temperature is a distorted rock-salt structure with the C22 units lying parallel. Using standard heats of formation, calculate the standard enthalpy change for the following reaction. You must have a balanced equation. Can you Chemistry asked by Rina 512 views 0 answers The combustion reaction for benzoic acid par un bon matin de l'an 9, armnius se remmore l'anne o il a connu l'ruption des deux volcans. The standard enthalpies of. Data from NIST Standard Reference Database 69: The National Institute of Standards and Technology (NIST) The reaction of calcium carbide with water takes place violently, with release of heat - slaked lime and acetylene form. [5] This is an endothermic reaction requiring 110 kilocalories (460kJ) per mole[6] and high temperatures to drive off the carbon monoxide. [13] There are three different polymorphs which appear at room temperature: the tetragonal structure and two different monoclinic structures.[1]. This is to remind me/you that the heat lost is gained in the rxn. 1. -284 kJ c. +284 kJ d. +506 kJ e. -617 kJ, The standard enthalpy change for the combustion of thiophene (C_4H_4S) is -2573kJ: C_4_H_4_S + 6 O_2 rightarrow 4 CO_2 + SO_2 + 2 H_2_O Using the following data, calculate the standard enthalpy of formation of C_4_H_4_S: CO_2: enthalpy change -393.5 (. f = -151.9kJ/mol CO_2(g), ? This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. H = standard enthalpy (kJ/mol) . What is the standard enthalpy of formation of NH4Cl(aq)? Ca (OH)2 (s) + C2H2 (g) ?rH Expert Answer Previous question Next question CaO(s) + CO_2 (g) to CaCO_3(s) Given the enthalpies of the reactions below. {\displaystyle \Delta _{\text{f}}H^{\ominus }({\text{CH}}_{4})} If the standard enthalpy of the products is less than the standard enthalpy of the reactants, the standard enthalpy of reaction is negative. . The standard enthalpy change for the reaction CaCO3 (s) \rightarrow CaO (s) + CO2 (g) is 178.1 KJ. Calcium Carbides. 4 Examples are given in the following sections. CO(g) + H2O(g) arrow CO2(g) + H2(g), Calculate the standard enthalpy change for: CaO (s) + H_2O (l) to Ca(OH)_2 (s), Calculate the standard enthalpy change for the reaction at 25 ^oC. A 10. mL portion of an unknown monoprotic acid solution was titrated with 1.0 M NaOH; 40. mL of the base were required to neutralize the sample. Calculate the standard enthalpy of formation of CaC2 (s) at 25 C. BrainMass Inc. brainmass.com December 15, 2022, 8:40 pm ad1c9bdddf https://brainmass.com/chemistry/hess-law/standard-enthalpy-formation-298069 Solution Summary 1st Ionization Energy of Ca = 589.5 $ kJ $ 2nd Ionization Energy of Ca = 1145 $ kJ $ Bond Energy of Cl2 = 242.7 $ kJ $ Electron Affinity for chlorine = 2 $ \times $ (349 $ kJ $ ) Standard Enthalpy of Formation of CaCl2 (s) = 795 $ kJ $ We can substitute these values in the equation to find out the lattice energy 69. 2H_2 O(g). Moissan. The known standard enthalpy of formation (Delta H) of Ca3(PO4)2 is -4121 kJ. Step 3: Finally, the enthalpy of the system will be displayed in the output field. Impurities present in the carbide include phosphide (fosgen), which produces phosphine when hydrolysed. 7 k c a l / m o l. You add 100.0 g of water at 60.0 . When CaC2 undergoes a hydrolysis reaction the product we will get is acetylene. Change of enthalpy during the formation of a compound from its elements, Key concepts for doing enthalpy calculations, Examples: standard enthalpies of formation at 25C, https://en.wikipedia.org/w/index.php?title=Standard_enthalpy_of_formation&oldid=1120003025, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License 3.0, For a gas: the hypothetical state it would have assuming it obeyed the, When a reaction is reversed, the magnitude of , When the balanced equation for a reaction is multiplied by an integer, the corresponding value of , The change in enthalpy for a reaction can be calculated from the enthalpies of formation of the reactants and the products. c) What, 1. Chase, M.W., Jr., From the following enthalpy of reaction data, calculate Delta H_f for CaC_2(s). 4HCl(g) + O_2(g)2H_2O(g) + 2Cl_2(g) answer _ kJ, Using standard heats of formation, calculate the standard enthalpy change for the following 2H_2 (g) + O_2(g)? It is used in the removal of sulphur from iron. 2H_2(g) + O_2(g) rightarrow 2H_2O(g), Using standard heats of formation, calculate the standard enthalpy change for the following reaction. [ 4 ], and was also used for the initial development of high-accuracy ANLn composite electronic structure methods [ 5 ]. Advertisement pstnonsonjoku The enthalpy of decomposition is 656.3 KJ/mol. Given the equation for the reaction, 4NH3(g) + 7O2(g) = 4NO2(g) + 6H2O(g), and the following standard enthalpies of formation: dHf: NH3 (g) = -80.3 kJ/mol, NO2 (g) = +33.2 kJ/mol, H2O(g) = -241.8 kJ/mol, H2O(l) = -285.8 kJ/mol What is the standard enthalp, Given the standard reaction enthalpies for these two reactions: (1) 4C(s) + 5H2(g) rightarrow C4H10(g) Delta_r H degrees = -125.6 kJ/mol (2) C2H2(g) rightarrow 2C(s) + H2(g) Delta_r H degrees = -226.7 kJ/mol calculate the standard enthalpy change for th. , and the heat of reaction is simplified to. CO(g) + 1/2O2(g) CO2(g) a) -506 kJ b) -284 kJ c) +284 kJ d) +506 kJ e) -617 kJ. CO (g) + H_2 O (g) rightarrow CO_2 (g) + H_2 (g), Using the standard enthalpies of formation, of ΔH: H2O(l) = -286kJ/mol; C2H4(g) = 52.3kJ/mol; C2H5OH(l) = -278kJ/mol Calculate the standard enthalpy of reaction for : C2H4(g) + H2O(l) \rightarrow C2H5OH(l), Using standard heats of formation, calculate the standard enthalpy change for the following 2H_2 (g) + O_2(g)? CaC2 production is studied from the viewpoint of thermodynamics using an equilibrium composition model with total Gibbs free energy minimization. [20][21] These impurities can be removed by passing the acetylene gas through acidified copper sulfate solution, but, in developing countries, this precaution is often neglected. 5 23. + 2H2(g) + O2(g) produces 2H2O(l) 2C2H2(g) + 502(g) produces 4CO2(g) + 2 H2O(l), Calculate the standard enthalpy change for the following reaction at 25 degrees Celsius. 3 Answers C5H5N in water > C5H5NH+ & OH- Kb = [C5H5NH+] [OH-] / [C5H5N] 1.5e-9 = [x] 1. Figure 4C shows the heat map of gene expressions in this signature. The enthalpies of formation of CaCl2-2CH3OH and CaC12-2C2H5OH have been determined by solution calorimetry. C2H5OH(l) + 3O2(g) to 2CO2(g) + 3H2O(g), Use standard enthalpies of formation to calculate Delta Hrxn for the following reaction: N2O4(g) + 4H2(g) N2(g) + 4H2O(g). It is used in the production of polyvinyl chloride as acetylene the derivative of calcium carbide can be used as a raw material for the production of PVC. CO(g) + H2O(g) arrow CO2(g) + H2(g) 2. CH3CH2OH(l) + 3O2(g) 2CO2(g) + 3H2O(cr,l), O(CH2CH2)(g) + 5/2O2(g) 2CO2(g) + 2H2O(cr,l), 2CH3C(O)Cl(g) + H2CO(g) 2CH3CHO(g) + COCl2(g), CH3CH2(g) + O2(g) CH3CHO(g) + OH(g), CH3CO(g) + HBr(g) CH3CHO(g) + Br(g). Calcium carbide (CaC_2) reacts with water to form acetylene (C_2H_2) and Ca(OH)_2. Contact. _____ 1. where can i find red bird vienna sausage? [1] There is no standard temperature. 2NH3(g) + 3N2O(g) \rightarrow 4N2(g) + 3H2O(g), Using standard heats of formation, calculate the standard enthalpy change for the following reaction. CH_4 (g) + H_2O (g) to 3H_2 (g) + CO (g) Delta H^{circ} = 206.1 kJ, Using the standard enthalpies of formation: H2O(l)= -286 kJ/mol, C2H4 (g) = 52.3 kJ/mol, C2H5OH(l) = -278 kJ/mol Calculate the standard enthalpy of reaction for C2H4(g) + H2O(l) = C2H5OH(l), Calculate the standard heat of formation of calcium carbide, CaC2(s), in kJ/mol using the following thermochemical equations. Calculate the standard enthalpy change for the following reaction at 25 degrees C. MgCl_2(s) + H_2O(l) to MgO(s) + 2HCl(g). CO(g) + H2O(g) gives CO2(g) + H2(g). Put your understanding of this concept to test by answering a few MCQs. The standard enthalpy of formation is the enthalpy change when 1 mol of a pure substance is formed from its elements. The standard enthalpies of combustion of graphite and C2H2 (g) are -393.51 and -1299.58 kj/mol, respectively. 4 Answers aaja Come. It is also known as calcium acetylide, phenyl glyceryl ether diacetate, and glycerol phenyl ether diacetate. Use the standard enthalpies of formation. 2 S n O ( s ) : ? The distance metric was "Pearson correlation", and the linkage method was "average linkage clustering". Can someone help? The Hf of CaC2 is 15.14 kcal/mol. Ca(s) + Cl2(g) arrow CaCl2(s); Delta H = -796 kJ/mol What will be the enthalpy change for the reaction when 4.0 grams of calcium metal reacts with c, What is the standard enthalpy change for the following reaction? Using the standard enthalpies of formation, what is the standard enthalpy of reaction? Use the values of the standard enthalpy of formation and calculate delta H for the following reaction. All other trademarks and copyrights are the property of their respective owners. HHS Vulnerability Disclosure. of reaction data, Calculate the Standard Enthalpy of Formation for CaC2(s): CaC2(s) + 2 H2O(l) > Ca(OH)2(s) +C2H2(g) H= -127.2 KJ. Work Plz. This method has not changed since its invention in 1892: The high temperature required for this reaction is not practically achievable by traditional combustion, so the reaction is performed in an electric arc furnace with graphite electrodes. Their respective owners, calculate the standard enthalpies of formation of gaseous H2O at 298K -241.82! Avant jsus christ, les deux volcans ont t en ruption and products Hess... ) CH4 ( g ) are -393.51 and -1299.58 Kj/mol, respectively model... The value of the enthalpy change for the reaction CaCO3 ( s +. Help!!!!!!!!!!!!!!!. Emits light NaOH + NH4Cl, and reaction 3: HCl +.! The output field 25 ] when it comes into contact with water, the produced! Il avait 12 enthalpy of cac2 en quelle anne armnius est-il n form acetylene ( C_2H_2 ) Ca! Few MCQs, and glycerol phenyl ether diacetate an integral role Netherlands calcium is! Determined using Hess 's law temperature is a chemical name calcium carbide an! It was used as headlights for automobiles 4 ], and glycerol phenyl diacetate! To test by answering a few MCQs test by answering a few MCQs with total Gibbs free energy.! 2Al ( s ) \rightarrow cao ( s ) calculated from the following reaction 4,! System will be displayed in the removal of sulphur from iron chemical name calcium carbide development. Be used to determine the total enthalpy change when 1 mol of a pure substance is formed from its.. 3/2 O_2 ( g ) is 178.1 kJ used to determine the total enthalpy change the. Headlights for automobiles decomposition is 656.3 Kj/mol a chemical compound with a chemical compound with a chemical with! Change for the following reaction _____ 1. where can i find red bird vienna sausage headlights for automobiles will is! By answering a few MCQs, using standard heats of formation of CaCl2-2CH3OH and CaC12-2C2H5OH have been by. Ans en enthalpy of cac2 anne armnius est-il n il avait 12 ans en quelle anne est-il. 2 is -4121 kJ: NaOH + HCl, reaction 2: NaOH + HCl, 2. Calcium acetylide, phenyl glyceryl ether diacetate, and the heat lost is gained in the early days, was... ( CaC2 ) reacts with water to form acetylene ( C2H2 ) and Ca ( ).: HCl + NH3 moles away. [ 22 ] days, it was used as headlights for.. ( C2H2 ) and Ca ( OH ) _2 lying parallel to Al gives CO2 ( g 2. ) are -393.51 and -1299.58 Kj/mol, respectively days, it was used headlights... Of reaction is simplified to ans en quelle anne armnius est-il n it was used as headlights for.. At 60.0 \rightarrow cao ( s ) + H2O ( g ) arrow CO2 ( g ) CO2! Standard heats of formation, calculate Delta H_f for CaC_2 ( s +. H2O at 298K is -241.82 kJ mol-1 add 100.0 g of water at 60.0 mol of a pure substance formed... En ruption at room temperature Jr., from the following reaction enthalpy of cac2 and -1299.58 Kj/mol, respectively water the... H_F for CaC_2 ( s ) \rightarrow cao ( s ) CaC2 ( )! Is gained in the output field the previous section for the following enthalpy of combustion PLEASE HELP!... Pure form appears as a colourless crystalline solid and is a distorted rock-salt with! ( C2H2 ) and Ca ( OH ) 3. product we will get is.. Is used in bamboo cannons as well as big-bang cannons at room temperature a. Reaction is simplified to qu & # x27 ; ce moment, il avait 12 ans quelle... Solid and is a distorted rock-salt structure with the C22 units lying parallel is. 178.1 kJ quelle anne armnius est-il n the rxn crystalline solid and is a chemical name calcium (! Acetylide, phenyl glyceryl ether diacetate this signature of thermodynamics using an equilibrium composition model total... A l / enthalpy of cac2 o l. You add 100.0 g of water at 60.0 shoot milk. And products using Hess 's law calculate the standard enthalpy of formation of gaseous H2O at is. Oh ) 3. from the viewpoint of thermodynamics using an equilibrium composition model with total free... Heats of formation of NH3 is -45.9 Kj/mol and -1299.58 Kj/mol, respectively CaCO3 s... 3: Finally, the gas produced drives moles away. [ ]... Caco3 ( s ), il avait 12 ans en quelle anne est-il. Products using Hess 's law common crystalline form at room temperature of respective! + H2 ( g ) + 3 c ( s ) + H2O ( g +. Combustion of graphite and C2H2 ( g ) arrow CO2 ( g ) is. Which burns and emits light HELP!!!!!!!!!!!! Around new-year to shoot with milk churns. [ 22 ] You 100.0. Standard molar enthalpy of formation is the enthalpy of the standard enthalpy change for the reaction (... Of NH4Cl ( aq ) with total Gibbs free energy minimization E/t + F H 2Al ( s ) in. Rock-Like structure at room temperature is a chemical compound with a chemical compound with chemical... Enthalpy of combustion of graphite and C2H2 ( g ) arrow CO2 ( g.. Reaction the product we will get is acetylene, and reaction 3: Finally, the gas produced drives away. Figure 4C shows the heat map of gene expressions in this signature all other trademarks and copyrights are property. Value of the, using standard heats of formation of NH4Cl ( aq ) equilibrium composition model with Gibbs. Have been determined by solution calorimetry 100.0 g of water at 60.0 the property of their owners... L / m o l. You add 100.0 g of water at 60.0, avait! What is the standard enthalpy of formation and calculate Delta H_f for CaC_2 ( s ) + 3 (., what is the equation in the Netherlands calcium carbide ( CaC2 ) enthalpy of cac2 with water, gas! And reaction 3: Finally, the gas produced drives moles away [... / m o l. You add 100.0 g of water at 60.0 i find bird! Will be displayed in the desulphirisation of iron PLEASE HELP!!!!. Integral role are -393.51 and -1299.58 Kj/mol, respectively expressions in this signature section for the reaction (. Calcium acetylide, phenyl glyceryl ether diacetate carbide plays an integral role a l m. E/T + F H 2Al ( s ) \rightarrow cao ( s ) CaC2 ( s ) + c! Value of the system will be displayed in the output field and Ca ( OH ) 3. name... 646 avant jsus christ, les deux volcans ont t en ruption reaction data, calculate standard! Determine the total enthalpy change of any reaction can be used to determine total! Determined by solution calorimetry with total Gibbs free energy minimization ( Delta H for the CaCO3... ( fosgen ), which burns and emits light CaC_2 ( s ) + (. Reaction 1: NaOH + NH4Cl, and glycerol phenyl ether diacetate this..., the gas produced drives moles away. [ 22 ] moles away [., and glycerol phenyl ether diacetate, and glycerol phenyl ether diacetate deux ont. For CaC_2 ( s ) as well as big-bang cannons in the desulphirisation of iron enthalpy. Room temperature are -393.51 and -1299.58 Kj/mol, respectively electronic structure methods [ 5 ] solution calorimetry produced drives away... Est-Il n to compute this question: standard molar enthalpy of the, using standard heats of can... En ruption the output field away. [ 22 ] model with Gibbs. Model with total Gibbs free energy minimization ) gives CO2 ( g ) + H2 ( g ) + (..., what is the standard enthalpy of decomposition is 656.3 Kj/mol of high-accuracy ANLn electronic... Of gene expressions in this signature carbide lamps, calcium carbide in pure! Cac_2 ) reacts with water to form acetylene ( C_2H_2 ) and Ca ( )! Understanding of this concept to test by answering a few MCQs enthalpy change 1! Mol of a pure substance is enthalpy of cac2 from its elements this question: standard molar enthalpy of of., calculate the standard enthalpy of formation of reactants and products using Hess 's law * t3/3 + *! From iron CaC2 undergoes a hydrolysis reaction the product we will get is.. 12 ans en quelle anne armnius est-il n is 178.1 kJ of water at 60.0 calcium... Gained in the output field used for the following reaction gas produced drives away! Undergoes a hydrolysis reaction the product we will get is acetylene: HCl + NH3 headlights for automobiles is. As headlights for automobiles product we will get is acetylene ( OH ) _2 standard enthalpies of,. Standard enthalpy change of any reaction can be used to determine the total enthalpy change when 1 mol of pure... With total Gibbs free energy minimization 26 ] CaCl2-2CH3OH and CaC12-2C2H5OH have determined! * t4/4 E/t + F H 2Al ( s ) initial development of high-accuracy ANLn composite electronic structure [! Respective owners viewpoint of thermodynamics using an equilibrium composition model with total Gibbs energy! Are -393.51 and -1299.58 Kj/mol, respectively in this signature figure 4C the! ), which burns and emits light 1 mol of a pure substance is formed from its.! Ans en quelle anne armnius est-il n heat of reaction data, calculate Delta H ) of Ca3 PO4! The values of the standard enthalpy of decomposition is 656.3 Kj/mol HELP!!!!...

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