R17 An electrolysis chamber

Aim: To give an idea of large scale industrial uses of electrolysis
  Illustration R17 has been included to show that electrolysis is not just of theoretical interest, but is used industrially on a large scale. The illustration shows a huge electrolysis chamber, in which impure (96-98%) copper is purified to 99.9 % copper. Copper metal with this purity has the high conductivity required for a wide range of electrical applications.
The illustration provides a link with transparencies R18 and R19, which discuss the electrolytic production of NaOH and Cl2.
Illustration R20 deals with electrolytic refining and extraction.