Elemental calcium is produced by the electrolysis of molen CaCl2.
What mass of calcium can be produced by this process if a current of 8500 A is applied for 39 h? Assume that the electrolytic cell is 65% efficient. I found the mass to equal 1.6 x10^5g Ca, and that is correct.
It’s part B that I’m struggling with. What is the total energy requirement for this electrolysis if the applied emf is + 5.20 V?
I keep getting 1100 kWh, but it’s saying that it’s incorrect.
I did (1.6 x 10^5g)(1 mol Ca/40.078 g Ca)(2 mol e-/1 mol Ca)(96,485 C/1 mol e-)
(770, 377, 763.4 V)(5.20 V)(1 J/1C-V)(1 kWh)(3.6 x 10^6 J)=1100 kWh
What am I doing wrong?
This was for online homework that was due tonight, and the answer is .43 kWh, but I'd still like to know how to get this answer. Thank you!!
To find the total energy requirement for the electrolysis process, we need to consider the total charge (Q) passed through the cell and the applied electromotive force (emf). The formula for calculating the energy (E) is:
E = Q * emf
Let's break down the calculation step by step.
1. Calculate the total charge (Q):
Q = I * t
Given:
Current (I) = 8500 A
Time (t) = 39 h
Q = 8500 A * 39 h
Q = 331,500 Coulombs
2. Calculate the energy (E):
E = Q * emf
Given:
emf = 5.20 V
E = 331,500 C * 5.20 V
E = 1,723,800 Joules
3. Convert Joules to kilowatt-hours (kWh):
1 kWh = 3.6 x 10^6 Joules
E = 1,723,800 J * (1 kWh / 3.6 x 10^6 J)
E = 0.4783 kWh
Based on the calculation, the total energy requirement for this electrolysis process is approximately 0.4783 kWh, not 1100 kWh.
Please check your calculations and ensure that all the conversion factors are correct.