Question 12
The process that you saw in Activity 14.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?
Question 12
The process that you saw in Activity 14.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?
Copper ions are positively charged. They are attracted towards the plate which is connected to the negative terminal of the battery. As copper ions are transferred to the thin copper plate, this thin pure copper plate must be connected to the negative terminal of the battery. Consequently, impure copper rod is connected to the positive terminal of the battery.
Concept insight: When electric current is passed in this arrangement, copper ions from the solution get deposited on pure copper rod (attached to negative terminal) and copper ions from impure copper rod (attached to positive terminal) are liberated into the solution.
Copper ions are positively charged. They are attracted towards the plate which is connected to the negative terminal of the battery. As copper ions are transferred to the thin copper plate, this thin pure copper plate must be connected to the negative terminal of the battery. Consequently, impure copper rod is connected to the positive terminal of the battery.
Concept insight: When electric current is passed in this arrangement, copper ions from the solution get deposited on pure copper rod (attached to negative terminal) and copper ions from impure copper rod (attached to positive terminal) are liberated into the solution.
