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How does changing the functional used for density functional theory calculations affect the predicted electronic properties (such as band gap, work function, and binding energy) of a specific material?

asked 4 days ago in Computational Chemistry by HeribertoBow (490 points)

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Calculate the standard enthalpy change (ΔH°) for the reaction where 50.0 mL of 2.0 M hydrochloric acid reacts with 50.0 mL of 2.0 M sodium hydroxide to form 50.0 mL of 2.0 M sodium chloride and water, given that the density of the solutions is 1.00 g/mL and the specific heat capacity of the solutions is 4.18 J/g·°C.

asked 4 days ago in Chemical thermodynamics by RoryDelacruz (210 points)

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Can you balance the following chemical equation: Fe + O2 -> Fe2O3 Show the balanced equation with the coefficients of the reactants and products.

asked 4 days ago in Chemical reactions by AndersonPant (550 points)

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1 answer 37 views

Calculate the standard enthalpy change for the formation of methane gas (CH4) from its elements carbon (solid, graphite) and hydrogen gas (H2) given the following data:ΔHf° (C(graphite)) = 0 kJ/molΔHf° (H2(g)) = 0 kJ/molΔHc° (CH4(g)) = -890.4 kJ/mol

asked 4 days ago in Chemical thermodynamics by UFCLaverne11 (470 points)

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Calculate the polarization of a copper-silver galvanic cell in which the concentration of copper ions is 0.5 M, the concentration of silver ions is 0.1 M, and the cell is operating at a temperature of 25°C. The potential difference of the cell is measured to be 0.75 V.

asked 4 days ago in ElectroChemistry by TUOCaitlyn4 (490 points)

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Calculate the standard enthalpy change for the formation of 2 moles of water vapor (H2O(g)) if the combustion of 1 mole of methane gas (CH4(g)) results in the formation of 2 moles of water vapor and 1 mole of carbon dioxide gas (CO2(g)). Given that the standard enthalpy change of combustion of methane is -890.4 kJ/mol.

asked 4 days ago in Chemical thermodynamics by JuliannJfv26 (450 points)

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1 answer 40 views

Calculate the standard enthalpy and entropy change for the reaction, given the following information:2 H2(g) + O2(g) → 2 H2O(g)∆H°f [H2O(g)] = -241.8 kJ/mol∆H°f [H2(g)] = 0 kJ/mol∆H°f [O2(g)] = 0 kJ/mol∆S° [H2O(g)] = 188.8 J/Kmol∆S° [H2(g)] = 130.7 J/Kmol∆S° [O2(g)] = 205.2 J/KmolAssuming that all heat capacities are independent of temperature, calculate ∆S°rxn and ∆H°rxn for this reaction.

asked 4 days ago in Inorganic Chemistry by HugoHogg5769 (430 points)

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What is the role of chaperone proteins in the folding process of newly synthesized proteins and how do they assist in preventing misfolding or aggregation?

asked 4 days ago in BioChemistry by SusanHedges4 (310 points)

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Consider the following compound: 3,5-dimethylphenol. Using the protecting group strategy, propose a synthetic route for converting 3,5-dimethylphenol to 3,5-dimethylbenzoic acid. Include all necessary reagents and reaction conditions.

asked 4 days ago in Organic Chemistry by PatriciaOsbu (570 points)

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Calculate the standard free energy change (∆G°) for the following redox reaction at 25°C:2 Fe³⁺(aq) + 3 H₂(g) → 2 Fe(s) + 6 H⁺(aq)

asked 4 days ago in Chemical thermodynamics by FrancescoSgp (470 points)

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1 answer 33 views

Calculate the standard entropy change for the reaction: 2H2 (g) + O2 (g) -> 2H2O (g) given the standard enthalpy of formation of H2O (g) is -241.8 kJ/mol at 298 K.

asked 4 days ago in Inorganic Chemistry by MelindaPolen (610 points)

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1 answer 35 views

Calculate the standard enthalpy change for the reaction in which 50.0 mL of 1.0 M HCl is mixed with 50.0 mL of 1.0 M NaOH in a constant pressure calorimeter using the following data: the temperature of the HCl and NaOH solutions are both initially 25.0 °C, and the temperature of the mixture increases to 32.0 °C. The specific heat of the solution is 4.18 J/(g·°C) and the density of the solution is 1.00 g/mL. The reaction is: HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

asked 4 days ago in Chemical thermodynamics by Willie039449 (490 points)

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1 answer 33 views

Calculate the standard enthalpy of hydrolysis for Na2CO3 when 2.5 moles of water react with 1 mole of Na2CO3, given that the heat of reaction is -843.2 kJ/mol.

asked 4 days ago in ThermoChemistry by MarilouMarco (450 points)

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1 answer 48 views

How does changing the molecular weight of a polymer affect its melt viscosity and how can this be quantitatively measured using rheological measurements such as shear rate and shear stress?

asked 4 days ago in Polymer Chemistry by ElvindeCaste (470 points)

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1 answer 32 views

Calculate the standard potential of the cell Ag(s) | Ag+(aq, 0.0100 M) || Cu2+(aq, 1.00 M) | Cu(s) at 25°C.

asked 4 days ago in ElectroChemistry by BobFryer6357 (410 points)

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1 answer 34 views

Calculate the standard enthalpy change for the vaporization of 15 grams of water at its boiling point, given that the molar enthalpy of vaporization of water is 40.7 kJ/mol.

asked 4 days ago in Chemical thermodynamics by AstridCrooke (410 points)

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1 answer 32 views

Calculate the standard molar entropy change (∆S°) at 298 K for the reaction: 2H2 (g) + O2 (g) → 2H2O (l) given that the standard molar enthalpy change (∆H°) for this reaction is -572 kJ/mol.

asked 4 days ago in Quantum Chemistry by ClayRuggiero (410 points)

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1 answer 33 views

Calculate the standard enthalpy of formation of potassium nitrate (KNO3) given the following information:- Heat of combustion of potassium is -468 kJ/mol- Heat of combustion of nitrogen is -940 kJ/mol- Heat of combustion of oxygen is -283.8 kJ/mol- Heat of formation of KNO3 is -383 kJ/mol.

asked 4 days ago in Chemical thermodynamics by Ricardo42K0 (430 points)

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1 answer 29 views

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 4 days ago in Chemical engineering by LPFVirgie959 (590 points)

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Calculate the standard enthalpy of formation of methane gas (CH4) given the standard enthalpies of formation for carbon dioxide (CO2) (-393.5 kJ/mol) and water vapor (H2O) (-241.8 kJ/mol).

asked 4 days ago in ThermoChemistry by ErnestinaB30 (410 points)

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