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What is the pH of a solution with a hydrogen ion concentration of 4.2 x 10^-5 M? Use a pH meter to determine the pH of the solution and compare it to the theoretical value calculated using the Henderson-Hasselbalch equation.

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

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What is the equilibrium constant (Kc) for the reaction between potassium permanganate (KMnO4) and sulfur dioxide (SO2) in aqueous solution, given that sulfur dioxide is a weak reducing agent? Calculate the value of Kc at a temperature of 298 K.

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

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What is the standard enthalpy change for the reaction between 1 mol of ethanoic acid and 1 mol of sodium hydroxide in aqueous solution, given that the reaction produces 1 mol of sodium ethanoate and 1 mol of water?

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

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What is the standard enthalpy change for the phase transition reaction of water from ice to liquid at 25°C and 1 atm pressure?

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

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What is the Gibbs free energy change for the electrochemical reaction when a copper electrode is placed in a 1 M copper(II) sulfate solution and a standard hydrogen electrode (SHE) is placed in a 1 M hydrogen ion solution at 25°C?

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

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What is the Gibbs free energy change (ΔG) for the reaction, given the standard Gibbs free energy change (ΔG°) and the reaction quotient (Q)? For example, for the reaction A + B → C, if ΔG° is -100 kJ/mol and Q is 0.5, what is the ΔG for the reaction?

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

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1 answer 107 views

What is the enthalpy change when 1.50 moles of methane (CH4) is burned in excess oxygen gas (O2) under standard conditions, if the combustion reaction releases 890.4 kJ of heat? (Assuming all reactants and products are in their standard states)

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

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What is the enthalpy change for dissolving 10 grams of sodium chloride (NaCl) in 100 mL of water at 25°C? The heat capacity of water is 4.18 J/(g·°C) and the enthalpy of formation of NaCl is -411.1 kJ/mol.

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

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Using quantum chemistry calculations, analyze the effects of solvent polarity on the intermolecular interactions between ethanol and water molecules in a mixture, and explain how it influences the solubility of ethanol in water.

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

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What is the heat of sublimation of dry ice (CO2) when 60 grams of it is sublimated at a constant pressure of 1 atm? The initial temperature of dry ice is -78.5°C and its final temperature is -56.6°C.

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

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What is the standard enthalpy change for the vaporization of 50g of water at 100°C, given that the molar enthalpy of vaporization of water is 40.7 kJ/mol?

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

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What is the theoretical yield of p-nitroaniline that can be obtained from the reaction of 5 grams of aniline with excess nitric acid, assuming complete conversion and 100% yield?

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

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What is the theoretical yield of benzocaine that can be produced from 5 grams of p-aminobenzoic acid and excess ethanol in the preparation process?

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

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What is the formal charge of the nitrogen atom in the molecule HCN? Show your calculations.

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

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What is the enthalpy change when 50 g of NaOH is dissolved in 500 mL of water at 25°C? Consider the density and specific heat capacity of water, and use the standard enthalpy of formation values for NaOH and H2O.

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

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How can we control the rate of phosphorescence decay in a particular phosphorescent material under different temperature and light intensity conditions?

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

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What is the heat of hydration for the reaction between magnesium sulfate heptahydrate (MgSO4•7H2O) and water (H2O) when 3.50 g of MgSO4•7H2O is dissolved in 50.0 mL of water at 25 °C? The molar heat of hydration for MgSO4•7H2O is –90.39 kJ/mol.

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

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What is the theoretical yield of aspirin that can be obtained from the reaction of 2.0 grams of salicylic acid and 5.0 mL of acetic anhydride? Provide your answer in grams and show your calculations.

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

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How can we control and optimize the fluorescence properties of quantum dots through photochemical processes?

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

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1 answer 115 views

How does the Wagner-Meerwein rearrangement occur and what are its key characteristics? Explain with the help of a specific example from organic chemistry.

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

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