Electrolysis Flashcards
What does Electrolysis stand for?
Electro: Electricity
Lysis: To break down
So it basically means breaking down with electrolysis
What happens during electrolysis (In the electrodes)
1) An electric current is passed through the electrolyte (A molten or dissolved ionic compound) The ions move towards the electrodes, where they react and the compound decomposes
What is an electrolyte
This is an ionic compound that is molten or dissolved
What happens during electrolysis (with the positive and negative electrons)
The positive ions in the electrolyte will move towards the cathode (-ve electrode) and gain electrons (They are reduced)
The negative ions in the electrolyte will move towards the anode (+ve electrode) and lose electrons (they are oxidised)
Once the ions gain or lose electrons, they form uncharged elements and are discharged from the electrolyte
Why can ionic solids only be electrolysed if they are molten
This is because the ions can move freely and can conduct electricity
What happens to the ions in an molten ionic compound during electrolysis
The positive metal ions become positive at the cathode was they lose their electrons
The negative non-metal ions are oxidised to the element at the anode
What sort of metals have to be extracted from their ores using electrolysis
If a metal is above carbon on the reactivity series or reacts with carbon. If it is above carbon in the reactivity series, then the reduction reaction will not work
Out of the cathode and anode, which one is negative and which one is positive (which one is on the left, and which one is on the right)
The anode on the left, on the side of the positive charge on the battery. The non-metal heads to this side
The cathode is on the right, on the side of the negative charge on the battery. The metals are attracted to this side
Why are electrolysis of aqueous solutions different to electrolysis of molten ionic solids
There will be ions in the water, likely hydrogen and hydroxide ions
