what current (in amperes) is required to plate out 2.85 g of Cr from a Cr^3+ solution in a period of 2.50 hr?
Is the answer 1.76 A?
Thank you!
yes
To determine the current required to plate out 2.85 g of Cr from a Cr^3+ solution in 2.50 hours, we need to use Faraday's law of electrolysis.
Faraday's law states that the amount of substance (in moles) deposited or liberated at an electrode is directly proportional to the quantity of electricity (in coulombs) that passes through the electrolyte.
The formula to calculate the amount of substance deposited is:
Mass of substance (g) = (Current (A) × Time (s) × Molar mass (g/mol)) / (Faraday's constant (C/mol))
First, we need to determine the molar mass of chromium (Cr), which is 52.00 g/mol.
Next, we need to calculate the Faraday's constant (F), which is approximately 96,485 C/mol.
Now we can rearrange the formula to solve for the current (I).
I = (Mass of substance (g) × Faraday's constant (C/mol)) / (Time (s) × Molar mass (g/mol))
Plugging in the given values:
Mass of substance = 2.85 g
Time = 2.50 hours = 9000 seconds
I = (2.85 g × 96,485 C/mol) / (9000 s × 52.00 g/mol)
By simplifying the equation and performing the calculation, the current required to plate out 2.85 g of Cr from the solution in a period of 2.50 hours is approximately 1.05 A (amperes).