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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 enthalpy change for the combustion of propane?

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

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What is the entropy change (∆S) for the reaction: 2H2(g) + O2(g) → 2H2O(l) given the standard entropy values ∆S°(H2(g)) = 130.6 J/K·mol ∆S°(O2(g)) = 205.0 J/K·mol ∆S°(H2O(l)) = -69.9 J/K·mol

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

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Sure! Here's a precise problem for the student:The combustion of 2.50 grams of methane (CH4) gave off 119.1 kJ of heat. Calculate the enthalpy change for the combustion of one mole of methane at constant pressure.

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

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How can the use of polymer-based optical materials enhance the performance of organic solar cells, and what are the specific properties that make these materials effective in this application?

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

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What is the enthalpy change when 2.5 moles of methane are burned completely in excess oxygen gas, given that the enthalpy of combustion of methane is -890 kJ/mol?

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

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What is the amount of heat (in joules) required to raise the temperature of 125 grams of water from 25°C to its boiling point of 100°C? The specific heat capacity of water is 4.184 J/(g·°C) and the enthalpy of vaporization of water is 40.7 kJ/mol.

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

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What are the possible reasons for a student to encounter difficulties in understanding the periodic table and chemical elements?

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

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What is the standard enthalpy change for the dissolution of 2.5 moles of sodium chloride in water at 25°C, given that the standard enthalpy of formation of NaCl is -411.1 kJ/mol, and the molar heat capacity of the solution is 4.18 J/g K?

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

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What methods can be used to reduce the environmental impact of industrial waste disposal, and how do these methods compare in terms of effectiveness and feasibility in different industries and geographic locations?

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

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What is the enthalpy change when 10 g of potassium chloride (KCl) is dissolved in 100 mL of water at 25°C? The molar enthalpy of solution of KCl is -17.6 kJ/mol.

asked Mar 1 in ThermoChemistry 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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How can we increase the exposure of chemistry in our everyday lives to promote learning and interest in the subject among students?

asked Mar 1 in Chemical education 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 energy of the vibrational mode that gives rise to an absorption band at 1712 cm$^{-1}$ in the IR spectrum of a molecule of acetic anhydride (C$_4$H$_6$O$_3$)?

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

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What is the heat of hydration for the dissolution of 10 grams of calcium chloride in 200 mL of water at a temperature of 25 degrees Celsius? Given that the heat of hydration of calcium chloride is -82.8 kJ/mol.

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

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What is the formal charge of the carbon atom in the compound CH3COOH? Show your calculations.

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

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What is the theoretical yield of acetylsalicylic acid that can be produced from 5 grams of salicylic acid and an excess amount of acetic anhydride in the synthesis process, assuming 100% conversion and purity of the reaction?

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

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How to use quantum chemistry methods to accurately predict the electronic and magnetic properties of a selected transition metal complex, considering factors such as ligand field effects, coordination number, oxidation state, and spin state?

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

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What are the available techniques for assessing the compatibility of polymer blends and provide a critical evaluation of the strengths and limitations of each technique?

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

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