Question

Can Someone Please Check My Work?
Question Details
I'm worried because it doesn't seem right.

Will rate LifeSaver:

These are my trial numbers:
Initial mass of copper anode: 36.04 g
Initial mass of copper cathode: 34.89 g
Time of electrolysis: 15 Min.
Current: .5 amp
Final mass of copper anode: 36.02g
Final mass of copper cathode: 35.41g

1. Mass of copper oxidized at anode (g)
= 36.04g – 35.89g = .15g

2. Moles of copper oxidized (mol)
= .15/63.55 = .0024 mol

3. Moles of electrons transferred (mol e-)
Cu(s) => Cu2+(aq) + 2 e-
= 2 x .0024 = .0048 mol

4. Coulombs passed through cell (C) = Current (in Amperes) x time(in seconds)
= Current (in Amperes) x 15 x 60
.5 x 15 x 60 = 450

5. Electrons passed through cell (e-)
450 / 1.6 x 10-19 = 2.8 x 1021

6. Avogadro's number (e-/mol e-)
2.8 x 1021 / .0048 mol = 5.8 x 10²³

7. Average value of Avogodro's number = Average of all yourcalculated values for Avogadro's number:
My total from another trial for this question was 1.7 x 10²³ so myaverage is:
5.8 x 1021 + 1.7 x 10²³ = 7.57 x 1023 / 2 = 3.8 x 10²³

8. Literature value of Avogodro's number =
6.02 x 1023/mol
9. Percent Error = 100% x (Average value of Avogadro's number -Literature value of Avogadro's number)/Literature value ofAvogadro's number:
100(3.8 x 1023 – 6.02 x 1023) / 6.02 x 1023 = -37%

10. Faraday constant (C/mol e-) = Coulombs passed throughcell/Moles of electrons transferred.
450 / .0048mol = 93750 coulombs

11. Average Faraday constant (C/mol e-) = Average of all yourcalculated values for Faraday constant:
My total from another trial was 26842 coulombs so my averageis:
93750 coulombs + 26842 coulombs / 2 = 60296 coulombs

12. Literature value of Faraday constant = 96485 coulombs

13. Percent error:
100%( 60296 – 96485) / 96485 = - 37.5%

Also, do you know the answers to these?

I also need to answer these questions:
14. Repeat calculation of Avogadro’s number using the mass gain ofthe cathode instead of the mass loss of the anode. Account for anydifference in the calculated values.
15. Account for the percent errors in determining Avogadro’s numberand the Faraday constant.