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Calculate the standard enthalpy change for the fusion reaction of solid lithium at its melting point, assuming that the reaction is carried out under standard conditions.
asked
Feb 3
in
Chemical thermodynamics
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UteKqe974841
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1.9k
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0
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1
answer
68
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Calculate the standard enthalpy change and entropy change for the reaction: 2Fe(s) + 3/2O2(g) -> Fe2O3(s) Given the standard enthalpies of formation of Fe(s), O2(g), and Fe2O3(s) are -0.44 kJ/mol, 0 kJ/mol, and -826 kJ/mol, respectively. Also, the standard molar entropy of Fe2O3(s) is 87.4 J/(mol K).
asked
Feb 3
in
Inorganic Chemistry
by
AdeleStrothe
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2.1k
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0
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1
answer
65
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Calculate the standard enthalpy change for the reaction: 2Fe(s) + 3/2 O2(g) -> Fe2O3(s) given that the standard enthalpy of formation for Fe2O3(s) is -824.2 kJ/mol and that of Fe(s) is 0 kJ/mol.
asked
Feb 3
in
Chemical thermodynamics
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JackH2065356
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1.1k
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0
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1
answer
62
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Calculation of standard enthalpy change for the combustion of propane.If 5 moles of propane react completely in a bomb calorimeter under standard conditions, calculate the standard enthalpy change for the combustion of propane. The balanced chemical equation for the combustion of propane is:C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) Given the standard enthalpy of formation at 25°C and 1 atm for C3H8(g), CO2(g), H2O(g) are -103.8 kJ/mol, -393.5 kJ/mol and -241.8 kJ/mol respectively.
asked
Feb 3
in
Chemical thermodynamics
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AlfonsoJanze
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1.9k
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0
votes
1
answer
62
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Calculate the yield of ibuprofen obtained from the given starting materials (2-methylpropylbenzene and carbon dioxide) during the synthesis process.
asked
Feb 3
in
Chemical synthesis
by
TiffaniWymar
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1.6k
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0
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1
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64
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Calculate the standard enthalpy change of formation of magnesium oxide (MgO) using the following data: ΔH°f for Mg (s) = 0 kJ/molΔH°f for O₂ (g) = 0 kJ/mol ΔH°c for MgO (s) = -601.8 kJ/mol
asked
Feb 3
in
Chemical thermodynamics
by
AntonioDaven
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1.7k
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0
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1
answer
41
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Design a heat exchanger for a chemical plant which produces 1000 kg/hr of a chemical at a temperature of 350°C. The chemical needs to be cooled down to 50°C using water at an inlet temperature of 25°C. The cooling water flow rate should not exceed 5000 kg/hr. The overall heat transfer coefficient should be at least 500 W/m2K. Determine the surface area of the heat exchanger required for this process.
asked
Feb 4
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Chemical engineering
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CorineSasaki
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1.8k
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0
votes
1
answer
64
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Calculate the standard enthalpy change for the transition of liquid water at 100°C to steam at the same temperature, given that the enthalpy of vaporization of water is 40.7 kJ mol-1.
asked
Feb 3
in
Chemical thermodynamics
by
MellisaOlivo
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1.9k
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0
votes
1
answer
59
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Design a distillation column for the separation of a binary mixture of ethanol and water, with a feed consisting of 50 weight percent ethanol and 50 weight percent water. The column should be able to produce a distillate product containing at least 90 weight percent ethanol, with a recovery of at least 95 weight percent of the ethanol in the feed. The feed rate is 1000 kg/hr and the reflux ratio should be optimized for the best separation efficiency. Determine the number of theoretical trays required for the column design and calculate the heat load required for the operation of the column.
asked
Feb 3
in
Chemical engineering
by
HowardAlmond
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1.8k
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0
votes
1
answer
67
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Calculate the standard enthalpy change (ΔH°) for the reaction:2H2(g) + O2(g) → 2H2O(g)given the following bond energies:H-H = 436 kJ/mol, O=O = 498 kJ/mol, H-O = 463 kJ/mol
asked
Feb 3
in
Quantum Chemistry
by
BeverlyNavar
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1.8k
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0
votes
1
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12
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How can chemistry students obtain relevant and practical experience to adequately prepare for chemistry-related careers?
asked
Feb 5
in
Chemical education
by
Patsy0696347
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1.8k
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0
votes
1
answer
62
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Calculate the standard free energy change for the following redox reaction: Balanced Chemical Equation: 2Fe3+(aq) +3H2O2(aq) → 2Fe2+(aq) + 3O2(g) + 6H+(aq)Given data: Standard reduction potential of Fe3+/Fe2+ = +0.77 V Standard reduction potential of H2O2/O2 = +0.70 V
asked
Feb 3
in
Chemical thermodynamics
by
QTHGenevieve
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1.7k
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0
votes
1
answer
60
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Consider the metalloprotein hemoglobin, which has four heme groups each coordinated to a single iron ion. Suppose that ferrous iron in the heme group of hemoglobin is oxidized to ferric state by reacting with hydrogen peroxide. Calculate the number of hydrogen peroxide molecules needed to oxidize all the iron ions of hemoglobin in a human body that has a total of 5 liters of blood, assuming the concentration of hemoglobin in blood is 15 grams per liter.
asked
Feb 3
in
Coordination Chemistry
by
SylviaPettey
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2.4k
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0
votes
1
answer
64
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Calculate the standard enthalpy change for the reaction that occurs when 4.50 grams of magnesium oxide reacts with excess hydrochloric acid, given the following information:2HCl(aq) + MgO(s) → MgCl2(aq) + H2O(l) ΔH = -120.3 kJ/molMolar mass of MgO = 40.31 g/molRound your answer to two decimal places.
asked
Feb 3
in
Chemical thermodynamics
by
MoseSiler86
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1.8k
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0
votes
1
answer
40
views
Design a heterocyclic compound using pyridine as a starting material and incorporating at least one nitrogen atom in the heterocyclic ring. Draw the reaction mechanism involved in the synthesis and explain the role of each reagent used in the synthesis.
asked
Feb 4
in
Organic Chemistry
by
DominickPlum
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2.5k
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0
votes
1
answer
61
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Calculate the total resistance of an electrochemical cell consisting of two half-cells where one half-cell has a copper electrode submerged in a 0.5 M CuSO4 solution, and the other half-cell has a zinc electrode submerged in a 1.0 M ZnSO4 solution. The copper electrode is connected to the zinc electrode through a salt bridge. The resistance of the salt bridge is 22 ohms, and the resistance of the copper and zinc electrodes are negligible.
asked
Feb 3
in
ElectroChemistry
by
CharmainRose
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2.2k
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0
votes
1
answer
62
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Calculate the standard enthalpy of formation of water using Hess's law and the following data:2H2(g) + O2(g) -> 2H2O(g) ΔH°rxn = -484 kJ/molH2(g) + 1/2O2(g) -> H2O(l) ΔH°rxn = -286 kJ/mol
asked
Feb 3
in
Chemical thermodynamics
by
MaximoVardon
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1.9k
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0
votes
1
answer
60
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Consider a zinc electrode in a concentration cell that is connected to a copper electrode through a salt bridge. During the electrolysis of an aqueous solution of ZnSO4, a current of 2.5 A is passed through the cell for 20 minutes. Calculate the mass of zinc deposited on the electrode during this time assuming 100% efficiency. (Molar mass of zinc = 65.38 g/mol)
asked
Feb 3
in
ElectroChemistry
by
AnjaAbt20068
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2.0k
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0
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1
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61
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Calculate the standard Gibbs free energy change for the electrochemical reaction of zinc and copper ions: Zn(s) + Cu2+(aq) → Cu(s) + Zn2+(aq)Given the following standard electrode potentials: E°(Cu2+(aq) + 2e- → Cu(s)) = 0.34 V E°(Zn2+(aq) + 2e- → Zn(s)) = -0.76 V Assume standard conditions (25°C and 1 atm pressure) and that the concentrations of the copper and zinc ions are both 1 mol/L.
asked
Feb 3
in
ElectroChemistry
by
WallaceMaria
(
2.4k
points)
0
votes
1
answer
11
views
How can chemistry students overcome the challenge of limited access to laboratory equipment and facilities?
asked
Feb 5
in
Chemical education
by
SusannahRose
(
1.3k
points)
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