Revise For Test After Easter Electrolysis Flashcards
What does the world electrolysis mean?
Splitting up using electricity.
What do we call the substance broken down by electrolysis?
Electrolyte.
What are electrodes made from?
Unreactive substances such as graphite or platinum.
How do negatively charged ions become neutral atoms in electrolysis?
They lose electrons.
what will be formed at the electrodes in the electrolysis of molten potassium chloride?
Potassium metal at the negative electrode.
Chlorine gas at the positive electrode.
What will be formed at the electrode in the electrolysis of copper chloride solution?
Copper at the negative electrode.
Chlorine gas at the positive electrode.
What do ionic compounds need to be molten or in solution to do electrolysis?
So the ions are free to move between the electrodes.
What happens at the negative electrode during electrolysis?
Positive ions gain an electron.
What is reduction?
Gaining of electrons.
What is oxidation?
Loss of electrons
Why do the electrodes need to be replaced in aluminium extraction?
Oxygen reacts with the carbon electrode making carbon dioxide and damaging it.
Why is cryloite used in aluminium extraction?
Lowers temperatures require for electrolysis as aluminium oxide has very high melting point.
During electrolysis of aluminium oxide what happens at the positive electrode?
Each oxide ion loses 2 electrons to become oxygen atoms.
During electrolysis of aluminium oxide what happens at the negative electrode?
Each aluminium ions gain 3 electrons to become aluminium atoms.
What are the products of the electrolysis of brine?
Chlorine gas.
Hydrogen gas.
Sodium hydroxide.
