Hot questions

0 votes

1 answer 69 views

A student needs to calculate the activation energy for a reaction that takes place at an electrode with a current density of 2.5 mA/cm² at a temperature of 25°C. The reaction has a transfer coefficient of 0.5 and a standard rate constant of 2.0 × 10⁻⁶ cm/s. The student has access to the necessary thermodynamic data for the reaction. What is the activation energy for this electrochemical reaction?

asked Jan 22 in ElectroChemistry by BeatriceJ11 (2.2k points)

0 votes

1 answer 73 views

A chemistry student wants to determine the concentration of a solution containing iron (III) ions. Using colorimetry, they measure the absorbance of the solution at a specific wavelength and plot a calibration curve with solutions of known iron (III) ion concentration. The student then measures the absorbance of their unknown solution at the same wavelength and uses the calibration curve to determine the concentration of iron (III) ions in the sample. What is the concentration of iron (III) ions in the unknown solution, in units of moles per liter?

asked Jan 22 in Analytical Chemistry by HughNewquist (2.4k points)

0 votes

1 answer 64 views

Assuming you have the equilibrium constant value for a given chemical equation, determine the concentration of products and reactants at equilibrium for the reaction: N2(g) + 3H2(g) ⇌ 2NH3(g); Kc = 6.0 x 10^2 at 500°C. If the initial concentration of N2 is 0.1 M and the initial concentration of H2 is 0.2 M, what is the concentration of NH3 at equilibrium?

asked Jan 22 in Chemical equilibrium by OrenGillingh (2.5k points)

0 votes

1 answer 65 views

A student wants to investigate the effect of volume change on the equilibrium position of the reaction 2SO2(g) + O2(g) ⇄ 2SO3(g). The initial equilibrium concentration of SO3 is 0.1 M at a constant temperature. The volume is reduced by half at equilibrium. Calculate the new equilibrium concentrations of SO2, O2 and SO3 assuming the equilibrium constant (Kc) of the reaction remains constant.

asked Jan 22 in Chemical equilibrium by RubyPeltier8 (2.7k points)

0 votes

1 answer 83 views

A battery consists of a Zinc electrode and a Copper electrode. Calculate the exchange current density at the Zinc electrode if the concentration of Zinc ion in its solution is 0.1 M and the potential difference between the electrodes is 1.5 V. The standard electrode potential for Zinc is -0.76 V and the transfer coefficient for the electrode reaction is 0.5.

asked Jan 22 in ElectroChemistry by BradCoz53277 (2.4k points)

0 votes

1 answer 68 views

A student needs to determine the diffusion coefficient of a gas in a liquid by measuring the rate of diffusion using a diffusion cell. If the student knows the initial concentration and final concentration of the gas in the cell, and the time it took for diffusion to occur, what is the diffusion coefficient of the gas in the liquid?

asked Jan 22 in Physical Chemistry by KraigFeldman (1.9k points)

0 votes

1 answer 72 views

A chemistry student wants to find out the effect on the equilibrium position when the volume of a reaction mixture is changed. They have an equilibrium mixture of hydrogen and iodine gases forming hydrogen iodide gas according to the equation:$$H_2 (g) + I_2 (g) \leftrightharpoons 2HI (g)$$At 298 K, the equilibrium constant for this reaction is 54.3. Initially, the reaction mixture contains 0.5 moles of hydrogen gas, 0.5 moles of iodine gas, and 0 moles of hydrogen iodide gas in a container of volume 2L. If the volume is reduced to 1L while maintaining the temperature at 298 K, what wi

asked Jan 22 in Chemical equilibrium by BradCoz53277 (2.4k points)

0 votes

1 answer 71 views

A gas-phase reaction A ⇌ B is known to have a rate constant of 0.05 L/mol/s at 300 K. If the initial concentration of A is 0.1 M and the system reaches equilibrium after 2 minutes, what is the concentration of B at equilibrium? (Assume constant pressure and ideal gas behavior)

asked Jan 22 in Physical Chemistry by WilburnMcCor (2.6k points)

0 votes

1 answer 35 views

Calculate the dipole moment of carbon dioxide (CO2) molecule using ab initio calculations at the HF/6-311+G(d,p) level of theory. How does it compare to the experimentally measured dipole moment value? Explain the reason for any differences observed.

asked Jan 23 in Computational Chemistry by CarolynIan00 (2.5k points)

0 votes

1 answer 70 views

A sample of an inorganic compound contains 51.28% sodium, 21.44% sulfur, and 27.28% oxygen by mass. Determine the empirical formula of the compound.

asked Jan 22 in Inorganic Chemistry by KayleneThibo (2.4k points)

0 votes

1 answer 72 views

A chemistry student wants to determine the effect of adding a buffer to a solution containing acetic acid (CH3COOH) and its conjugate base (CH3COO-), which is in equilibrium with its ionized form (H+ and CH3COO-). The initial concentration of acetic acid is 0.2 M and the pH of the solution is 4.5. If the student adds a buffer solution containing equal amounts of acetic acid and sodium acetate (NaCH3COO), what will be the new pH of the solution and the extent of shift in equilibrium position?

asked Jan 22 in Chemical equilibrium by ElsieBidmead (2.4k points)

0 votes

1 answer 108 views

A student is given the unbalanced equation for the reaction between magnesium sulfate and sodium hydroxide in aqueous solution: MgSO4 + NaOH -> Mg(OH)2 + Na2SO4. The student needs to balance the equation and determine the coefficients for each compound.

asked Jan 21 in Inorganic Chemistry by TaneshaDoss0 (1.8k points)

0 votes

1 answer 67 views

A student needs to prepare 500 mL of a buffer solution with a pH of 7.5 using a weak acid HA and its conjugate base A-. HA has a pKa of 4.5 and its initial concentration is 0.2 M. What mass of HA and A- should be mixed to prepare the buffer solution?

asked Jan 22 in Chemical reactions by FBUToni29827 (2.9k points)

0 votes

1 answer 67 views

A student needs to find the enthalpy of polymerization of ethylene from the enthalpies of combustion of ethylene gas (-1411 kJ/mol) and polyethylene (-5120 kJ/mol). Calculate the enthalpy change, in kJ/mol, for the polymerization of ethylene gas to form polyethylene.

asked Jan 22 in ThermoChemistry by HenryWalden (2.3k points)

0 votes

1 answer 109 views

What is the major product(s) of the following nucleophilic substitution reaction between 1-bromopropane and sodium ethoxide in ethanol: 1-bromopropane + sodium ethoxide → ? + sodium bromide

asked Jan 21 in Organic Chemistry by ScottyWild8 (2.3k points)

0 votes

1 answer 64 views

A student wants to calculate the efficiency of an electrochemical cell with a standard potential of -0.74 volts. The cell is set up with a copper electrode immersed in a solution of copper(II) sulfate and a silver electrode immersed in a solution of silver nitrate, connected by a salt bridge. The student measures a current of 0.5 amperes flowing through the cell for a duration of 60 minutes. Calculate the efficiency of the electrochemical cell in terms of the amount of reactants consumed and the amount of product formed.

asked Jan 22 in ElectroChemistry by Dawn49061396 (2.6k points)

0 votes

1 answer 70 views

A gas phase reaction occurs according to the following equation: A(g) + 2B(g) -> C(g) + D(g)The reaction is carried out at a total pressure of 2 atm and at 298 K. The initial concentrations of A and B are 0.1 M and 0.2 M, respectively. The rate of formation of C is measured to be 0.02 M/s. What is the rate of disappearance of B?

asked Jan 22 in Physical Chemistry by RobtGranier (2.1k points)

0 votes

1 answer 70 views

A gas mixture contains equal parts of hydrogen and helium gases in a container at a temperature of 300 K. Determine the total internal energy of the gas mixture using the grand canonical ensemble model.

asked Jan 22 in Physical Chemistry by ChristalMahl (2.3k points)

0 votes

1 answer 67 views

A student needs to calculate the enthalpy change for a chemical reaction given the enthalpies of formation of the reactants and products. The specific problem is: Calculate the enthalpy change for the reaction:CH4(g) + 2O2(g) → CO2(g) + 2H2O(l)Given the following enthalpies of formation:ΔHf(CH4) = -74.8 kJ/molΔHf(CO2) = -393.5 kJ/molΔHf(H2O) = -285.8 kJ/mol

asked Jan 22 in Chemical reactions by Aline0805519 (2.3k points)

0 votes

1 answer 107 views

Balance the chemical equation for the inorganic compound calcium chloride reacting with sodium carbonate to form calcium carbonate and sodium chloride.

asked Jan 21 in Inorganic Chemistry by AltonDurden (2.4k points)

Page:

« prev
1
...
647
648
649
650
651
652
653
654
655
...
1000
...
next »

Hot questions

Hot questions

Categories