Electrolytic cell

background [prelab assignment: (10 points) due at the beginning of the lab]

determine the time to obtain 1.0 g solid Cu using an electrolytic cell containing Cu²⁺ with a current of 5.0 A.

hypothesis & basis  [see purpose]

purpose

compare:

• actual amount of copper plated onto a carbon electrode vs. theoretical amount
• experimental yield in high vs low [Cu²⁺ ] @ same current level & duration

materials

electrodes= Cu & C (student determines which is the cathode vs. anode,  i.e. how to connect electrodes to voltage source)

water; acidic solution of copper (II) sulfate (10 g CuSO₄ * 5 H₂O + 2.5 mL concentrated H₂SO₄ q.s. 100 mL)

variable power supply; balance; 100 mL volumeric flask

methods / data analysis

student design; recommend ~ 0.5 A @ 20 minutes, so plate ~ 200 mg Cu onto electrode

Content of the lab report [25 points]

hypothesis & basis

data table of your experimental measurements:  # gram Cu plated onto C electrode in high vs. low [Cu²⁺ ]

calculations for experimental & theoretical # grams of copper plated onto the carbon electrode

statistical analysis [see purpose] & interpretation, i.e. validity of your hypothesis 

error analysis:  compare theoretical vs. experimental amount of Cu plated onto electrode

resources:

lab activity source (examples):  site 1 & site 2  [access 4 / 2009]