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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 factors affect the absorption, distribution, metabolism, and excretion of drugs in the human body and how can medicinal chemists optimize a drug's pharmacokinetic properties to improve therapeutic efficacy?

asked Mar 1 in Medicinal Chemistry 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 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 optimal reaction conditions for the synthesis of p-nitroaniline from aniline and nitric acid, and how can the purity of the final product be measured and improved?

asked Feb 28 in Chemical synthesis by TheScientist (138k points)

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What are the specific difficulties that students face while understanding the periodic table? How can these issues be addressed to enhance the students’ learning and comprehension of chemical elements?

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

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What is the enthalpy change for the reduction of CuO using hydrogen gas, given that 2.50g of CuO (s) is reacted with 0.500L of H2 (g) at STP? The balanced chemical equation for the reaction is CuO (s) + H2 (g) -> Cu (s) + H2O (l).

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

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What is the enthalpy change for the reaction: 2H2(g) + O2(g) → 2H2O(l) given the following bond enthalpy values: H-H: 436 kJ/mol, O=O: 495 kJ/mol, H-O: 464 kJ/mol (assume that all gases are at standard conditions)?

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

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Identify the major intermediate(s) and propose a mechanism for the following reaction: CH3CH2OH + HBr → CH3CH2Br + H2O

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

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What is the bond energy (in kJ/mol) of the covalent bond between the carbon and oxygen atoms in carbon dioxide (CO2), given that the bond length is 116.3 pm?

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

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What is the VSEPR geometry of a molecule consisting of one central atom and five atoms attached to it, where the central atom has two lone pairs of electrons?

asked Feb 28 in Chemical bonding by TheScientist (138k points)

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What is the lattice energy of NaCl(s) at 25°C given that the enthalpy of formation of NaCl(s) is -411.2 kJ/mol, the enthalpy of sublimation of Na(s) is 107.29 kJ/mol, and the first ionization energy of Na(g) is 495.8 kJ/mol?

asked Mar 1 in Inorganic 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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What is the lattice energy of CaF2 in kilojoules per mole given that the distance between the calcium ion and fluoride ion is 2.01 Å and the charges on the ions are +2 and -1 respectively?

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

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What is the corrosion potential of a zinc electrode immersed in a solution of 0.1 M ZnSO4, which is coupled with a copper electrode in a 0.1 M CuSO4 solution at 25°C? Given that the standard reduction potential for Zn2+ is -0.76 V and for Cu2+ is +0.34 V.

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

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What are the main reasons for the difficulty in integrating technology into chemistry education, and what strategies can chemistry educators use to overcome these obstacles and effectively incorporate technology into their teaching methodologies?

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

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What is the formal charge on the oxygen atom in the sulfate ion (SO4²⁻)? Show the calculation of the formal charge.

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

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What is the enthalpy of vaporization of water at 100°C? Given that the vapor pressure of water at 100°C is 1 atm and the molar heat capacity at constant pressure of water is 75.3 J/mol*K. Also, assume that water behaves as an ideal gas.

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

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