Purifying Metals Aims: Describe the purification of copper by electrolysis Draw a simple diagram to the show the method used to purify copper

Copper How do you get copper? What is it used for?

Purifying Copper

Copper sulphate CuSO4 solution PURIFYING COPPER IMPURE COPPER ANODE PURE COPPER CATHODE Copper sulphate CuSO4 solution Cu2+ Cu2+ Copper atoms from impure copper are OXIDISED to copper ions Copper ions from impure copper are REDUCED to copper atoms Cu Cu2+ Cu Copper ions transported from anode to cathode As the atoms of the impurities are not transported, the copper that builds up on the cathode is extremely pure.

Why will the concentration of the solution stay the same? IMPURE COPPER ANODE PURE COPPER CATHODE IMPURE COPPER ANODE PURE COPPER CATHODE Over time, the impure anode dissolves away and the impurities sink to the bottom. The pure cathode grows as more pure copper is deposited on it. Why will the concentration of the solution stay the same?

Oxidation is loss, reduction is gain OILRIG Oxidation is loss, reduction is gain ‘OILRIG’ Na+ Na+ Cl- Cl- Na+ Na+ Cl- Cl- ions LOSING electrons to become atoms is called ‘OXIDATION’ (even though oxygen may not be involved) + ions GAINING electrons to become atoms is called ‘REDUCTION’

Purification: The half reactions Oxidation Is Loss of electrons, Reduction Is Gain (OILRIG) Anode (+ve electrode) Cu(s)  Cu2+(aq) + 2e- Cathode (-ve electrode) Cu2+(aq) + 2e-  Cu(s)

Copper is purified to improve its Copper is purified by Unscramble the words to end the sentences Copper is purified to improve its NOT CIVIC DUTY Copper is purified by CELERY IS LOST Pure copper forms at the DO TEACH Impurities form called A ODD MENU The anode will slowly DIVE LOSS At the cathode copper ions gain CORN STEEL conductivity electrolysis cathode anode mud dissolve electrons