Electrolysis and redox
3 marks · EasyThe diagram shows the essential parts of an apparatus for the electrolysis of molten magnesium chloride (MgCl).
What does it mean to 'discharge' a chloride ion (Cl) at the electrode?
State what happens to the charge of a chloride ion when it is discharged.
Describe briefly what is formed when chloride ions are discharged at the anode.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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(a) It means the ion loses its charge, usually by losing electron(s) to the electrode.
(b) It becomes neutral / loses its negative charge.
(c) Chlorine gas (Cl) is formed.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · States that discharge means losing its charge or electron(s) at the electrode.
B1 (b) · 1 mark · States the chloride ion becomes neutral / loses its negative charge.
B1 (c) · 1 mark · States that chlorine gas (Cl) is formed.
Worked solution
a) To discharge a chloride ion means it loses its charge by losing an electron to the electrode.
b) The chloride ion becomes neutral, losing its negative charge.
c) The discharged chloride atoms join to make chlorine gas (Cl).