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Calculate the amount of heat absorbed or released when 50 grams of NaCl crystals at 25°C are dissolved in 200 grams of water at the same temperature. Given the enthalpy of crystallization of NaCl is -787 kJ/mol and the specific heat capacity of water is 4.18 J/g°C.

asked Jan 23 in ThermoChemistry by YVMCinda4278 (2.3k points)

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1 answer 57 views

Calculate the amount of heat absorbed or released when 20 grams of dry ice (solid carbon dioxide) is converted to gaseous carbon dioxide at -78.5°C and atmospheric pressure, given the heat of sublimation of dry ice is 25.2 kJ/mol.

asked Jan 23 in ThermoChemistry by MichelleHall (2.0k points)

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1 answer 61 views

Calculate the amount of heat absorbed or released when 2.5 moles of sodium acetate (NaCH3COO) is crystallized from its solution at a constant temperature of 25°C. The heat of crystallization for sodium acetate is -427 kJ/mol.

asked Jan 23 in ThermoChemistry by WayneYcs587 (2.5k points)

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Calculate the amount of heat absorbed by 50 grams of water during the process of crystallization when it is cooled from 70°C to 0°C and solidifies into ice with a heat of crystallization of 333.55 J/g.

asked Jan 23 in ThermoChemistry by AguedaD83620 (2.6k points)

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1 answer 67 views

Calculate the amount of heat absorbed (in joules) when 10 grams of sodium hydroxide (NaOH) is dissolved in 100 mL of water at 25°C, given that the enthalpy of solution for NaOH is -44.51 kilojoules per mole.

asked Jan 23 in ThermoChemistry by MervinSchroe (2.0k points)

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1 answer 71 views

Calculate the amount of heat (in joules) released when 50 ml of 0.1 M hydrochloric acid (HCl) is mixed with 50 ml of 0.1 M sodium hydroxide (NaOH) at a constant pressure and a temperature of 25°C. The heat of neutralization of HCl and NaOH is -57.1 kJ/mol.

asked Jan 23 in ThermoChemistry by JeremiahMoli (1.7k points)

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1 answer 48 views

Calculate the amount of energy required to vaporize 100 grams of liquid water at its boiling point (100°C) given its enthalpy of vaporization is 40.7 kJ/mol.

asked Jan 23 in ThermoChemistry by MaximoVardon (1.9k points)

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1 answer 63 views

Calculate the amount of energy required to melt 50 grams of ice at 0°C, given the enthalpy of fusion for water is 6.01 kJ/mol.

asked Jan 23 in ThermoChemistry by MireyaFlaher (1.6k points)

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1 answer 55 views

Calculate the amount of energy required to completely desorb 2 moles of hydrogen molecules from a metal surface if the enthalpy of desorption for each H2 molecule is 436 kJ/mol.

asked Jan 23 in ThermoChemistry by RodrigoHopwo (1.9k points)

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1 answer 60 views

Calculate the amount of energy needed to desorb 10 moles of hydrogen gas from a metal surface, given that the enthalpy of desorption is -120 kJ/mol.

asked Jan 23 in ThermoChemistry by TiffaniWymar (1.6k points)

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1 answer 63 views

Calculate the amount of energy in Joules required to melt 15 grams of ice at 0°C, given that the heat of fusion of water is 334 J/g.

asked Jan 23 in ThermoChemistry by AntonioDaven (1.7k points)

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Calculate the amount of copper deposited on the cathode when a current of 5 amperes is passed through a copper sulfate solution for a duration of 30 minutes. The molar mass of copper is 63.55 g/mol and the Faraday constant is 96500 C/mol. The electrode area is 10 cm² and the copper sulfate solution has a concentration of 0.1 M. Assume 100% efficiency in the electrochemical reaction.

asked Jan 23 in ElectroChemistry by ChristianeBo (2.0k points)

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1 answer 51 views

Calculate the amount of chloride ions (Cl-) present in a 0.500 g sample of a sodium chloride (NaCl) solution using coulometry. The electric current used in the process was 2.26 A, and the time taken to completely react the sample was 120 s. The molecular weight of NaCl is 58.44 g/mol, and 1 mol of NaCl contains 1 mol of Cl-.

asked Jan 23 in Analytical Chemistry by MyrnaFaerber (1.8k points)

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Calculate the activation energy required for a chemical reaction to occur, given that the rate constant at 298 K is 4.70 x 10^-3 s^-1 and the rate constant at 313 K is 1.20 x 10^-2 s^-1. (Assume the Arrhenius equation applies.)

asked Jan 23 in Chemical reactions by JanisButterf (2.1k points)

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1 answer 58 views

Calculate the activation energy of the following electrochemical reaction: 2Fe^3+(aq) + 2I^-(aq) → 2Fe^2+(aq) + I2(s) Given that the reaction rate constant at 25°C is 1.0 × 10^-3 s^-1, and the reaction's activation energy follows the Arrhenius equation with a pre-exponential factor of 8.0 × 10^7 s^-1.

asked Jan 23 in ElectroChemistry by MartyKindler (1.5k points)

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1 answer 66 views

Calculate the activation energy of a reaction that has a rate constant of 8.23 x 10^-4 s^-1 at 300 K and a rate constant of 1.56 x 10^-2 s^-1 at 350 K.

asked Jan 23 in Chemical kinetics by KaitlynRodri (2.0k points)

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1 answer 67 views

Calculate the activation energy for the reaction between methane and oxygen to form carbon dioxide and water using density functional theory calculations.

asked Jan 23 in Computational Chemistry by WilburGuerre (2.3k points)

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1 answer 51 views

Calculate the activation energy for the reaction between hydrogen gas and iodine gas to form hydrogen iodide, given that the rate constant at 25°C is 4.2 × 10^-4 L/mol.s and the frequency factor is 1.5 × 10^12 s^-1.

asked Jan 23 in Chemical reactions by ScarlettRobb (1.7k points)

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1 answer 53 views

Calculate the activation energy for the following electrochemical reaction: 2H₂O(l) → O₂(g) + 4H⁺(aq) + 4e⁻ if the half-cell potentials are: E°(O₂/H₂O) = 1.23 V E°(H⁺/H₂) = 0 V Assuming the reaction follows Arrhenius equation, where the rate constant k is related to the activation energy Ea, temperature T and pre-exponential factor A by: k = A exp(-Ea/RT) where R is the gas constant equal to 8.314 J/molK.

asked Jan 23 in ElectroChemistry by ShaunBehan45 (2.8k points)

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1 answer 58 views

Calculate the activation energy for the electrochemical reaction of zinc and copper sulfate solution using the slope of the Tafel plot obtained from the data collected during a cyclic voltammetry experiment.

asked Jan 23 in ElectroChemistry by IFYRussel191 (2.2k points)

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