Electrolysis - Chemistry Unit 2 (C2 5.4) AQA

*Notes From The AQA GCSE TEXTBOOK and GCSE BITESIZE CHEMISTRY

See:

http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/ions/electrolysisrev1.shtml

for additional notes.

Electrolysis is the process by which ionic substances are decomposed (broken down) into simpler substances when an electric current is passed through them.

On the AQA Exam Board, the answer that will achieve full marks is:

Electrolysis means "splitting up using electricity. In electrolysis we use an electric current to break down an ionic substance. We call the substance broken down through the process of electrolysis the electrolyte.

This is the answer, copied from the AQA GCSE textbook ( New Specification). The question of simply defining the meaning of electrolysis is frequently asked in the exam.

For electrolysis to work, the ions must be free to move. Ions are free to move when an ionic substance is dissolved in water or molten (melted). For example, if electricity is passed through copper chloride solution, the copper chloride is broken down to form copper metal and chlorine gas.

DURING ELECTROLYSIS:

• Positively charged ions move to the negative electrode during electrolysis. They receive electrons…