How werer the lemons connected to each other and what type of circuit was it? also what created the reaction at the end?

Question: How werer the lemons connected to each other and what type of circuit was it? also what created the reaction at the end?
- Keywords:
  circuit,
  lemon,
  reaction,
  werer
Asked by to Thomas, Saiful, Piers, Meggi, Laurence, Karl, Javier, Chris on 9 Jan 2017. This question was also asked by Mod - Shane.
- Chris Eames answered on 9 Jan 2017:
  
  Each lemon had a copper nail and a magnesium strip pushed into it. The copper nail on one lemon was connected to the magnesium strip on the next lemon to form a series circuit.
  
  The reaction involved magnesium metal atoms giving up electrons and moving into the lemon juice as Mg2+ ions. The electrons then passed across through the copper nail and were picked up be hydrogen ions neat the copper electrode to liberate hydrogen gas.

Question: How werer the lemons connected to each other and what type of circuit was it? also what created the reaction at the end?