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What is the bond dissociation energy of the O-H bond in a water molecule? Use the given data: the enthalpy change for the reaction H2(g) + 1/2O2(g) --> H2O(l) is -285.8 kJ/mol and the average bond energy of an O-H bond is 463 kJ/mol.

asked Mar 1 in Chemical bonding by TheScientist (138k points)

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One mole of neon gas is heated at constant pressure, and its initial temperature is 300 K. The neon gas is then allowed to expand isothermally and reversibly until its volume triples. What is the entropy change of the neon gas during the process?

asked Mar 1 in Physical Chemistry by TheScientist (138k points)

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What is the entropy change for the combustion of methane (CH4) at constant pressure and standard conditions (298 K and 1 atm)?

asked Mar 1 in Chemical thermodynamics by TheScientist (138k points)

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Sure! Here is a question for the student to solve:What is the enthalpy change for the dissolution of 10 grams of potassium nitrate (KNO3) in 100 grams of water at 25°C? Given the molar enthalpy of dissolution for KNO3 to be -34.01 kJ/mol.

asked Mar 1 in ThermoChemistry by TheScientist (138k points)

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What is the lattice energy of CaF2 if the distance between calcium and fluoride ions in the crystal lattice is 2.40 Å and the charges on calcium and fluoride ions are +2 and -1, respectively?

asked Mar 1 in Inorganic Chemistry by TheScientist (138k points)

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How can we modify the synthesis technique for carbon nanotubes to increase their purity and homogeneity?

asked Mar 1 in Materials Chemistry by TheScientist (138k points)

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What is the heat required to sublimate 55 grams of dry ice (CO2) at -78.5°C and atmospheric pressure? The heat of sublimation of CO2 is 25.2 kJ/mol.

asked Mar 1 in ThermoChemistry by TheScientist (138k points)

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What is the enthalpy change for the combustion of methane gas (CH4) under standard conditions, given that the enthalpies of formation for CH4 and CO2 are -74.81 kJ/mol and -393.51 kJ/mol respectively?

asked Mar 1 in Chemical reactions by TheScientist (138k points)

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What are the specific molecular interactions between a particular drug and its target enzyme/protein, and how do these interactions lead to the desired therapeutic effect?

asked Mar 1 in Medicinal Chemistry by TheScientist (138k points)

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How effective are the United States Environmental Protection Agency's (EPA) regulations at protecting the environment from chemical pollutants?

asked Feb 28 in Environmental Chemistry by TheScientist (138k points)

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What is the standard enthalpy change for the combustion of 3 moles of propane gas (C3H8) at standard conditions? Express your answer in kJ/mol of propane burned.

asked Mar 1 in Chemical thermodynamics by TheScientist (138k points)

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What is the amount of heat energy required to vaporize 50 grams of water at its boiling point of 100°C, given that the enthalpy of vaporization of water is 40.7 kJ/mol?

asked Mar 1 in ThermoChemistry by TheScientist (138k points)

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What are the misconceptions that students commonly hold about chemical bonding and molecular structure, and how do they affect their ability to understand and predict chemical reactions?

asked Mar 1 in Chemical education by TheScientist (138k points)

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What is the formal charge of the sulfur atom in SO4^2- ion?

asked Mar 1 in Inorganic Chemistry by TheScientist (138k points)

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How can we calculate the energy states and optical properties of a semiconductor quantum dot with a 6 nm diameter and a spherical shape using quantum chemistry methods?

asked Mar 1 in Quantum Chemistry by TheScientist (138k points)

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What is the optimum amount of hexamethylenediamine to be used in the synthesis of nylon-6,6 from adipic acid to get maximum yield?

asked Mar 1 in Chemical synthesis by TheScientist (138k points)

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What is the enthalpy change when calcium chloride dihydrate (CaCl2•2H2O) is heated to release its water of hydration, given that the enthalpy of formation of CaCl2 is -795.8 kJ/mol and the heat capacity of CaCl2•2H2O is 155.09 J/(mol K)?

asked Mar 1 in ThermoChemistry by TheScientist (138k points)

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What is the heat of mixing when 20 ml of a 0.1 M HCl solution is added to 50 ml of a 0.2 M NaOH solution at room temperature, assuming complete mixing and a constant pressure?

asked Mar 1 in ThermoChemistry by TheScientist (138k points)

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How can we modify the synthesis methods for carbon nanotubes to achieve a longer tube length?

asked Mar 1 in Materials Chemistry by TheScientist (138k points)

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What is the theoretical yield of aspirin that can be obtained from the synthesis of 5 grams of salicylic acid using 10 mL of acetic anhydride assuming a 100% yield and purity?

asked Mar 1 in Chemical synthesis by TheScientist (138k points)

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