C6 Electrolysis Flashcards
What is molten
A substance in its liquid state. - water is in a molten state
What does inert mean
Unreactive
What are the electrodes made out of
Inert carbon graphite
What is an anion
A negative ion
What is a cation
Positive ion
What is the name of a positive ion
Cation
What is the name for a negative ion
Anion
What is a cathode
A negative electrode
What is an anode
Positive electrode
What is an electrolyte
A liquid or solution that can conduct electricty
What is electrolysis
Breaking down of a compound by electricity
What is the only element that is a non-metal and a liquid at room temperature
Bromine
What happens during electrolysis
An electric current is passed through an electrode. The ions move towards the electrodes where they react and the compound decomposes.
What is an electrode
A solid that conducts electricity and is submerged in the electrolyte
What will cations in the electrolyte move towards and why
The cathode because cations are positively charged and cathodes are negatively charged
What will anions in the electrolyte move towards and why
The anode because because anions are negatively charged and anodes are positively charged
Why cant an ionic solid be electrolysed
Because the ions are in fixed positions and cant move
Why can molten ionic compounds be electrolysed
Because the ions can move freely and conduct electricity
What can electrolysis be used to extract
A metal that is too reactive to be reduced with carbon
What is cryolite
An aluminium based compound with a lower melting point than aluminium oxide
What is allumium mixed with to lower its melting point
Cryolite
What does electrolysis extract Aluminium from
Extracts aluminium from the ore bauxite
What is the positive Al3+ ions attracted to and what happens due to this
They’re attracted to the negative electrode where they each pick up 3 electrons and turn into neutral aluminium atoms. These then sink to the bottom of the electrolysis
What are the negative O2- ions attracted to and what do they combine to form
They’re attracted to the positive electrode where they each lose two electrons. The neutral oxygen atoms will then combine to form O2 molecules
What happens at the negative electrode
Reduction occurs- a gain of electrons
What happens at the positive electrode
Oxidation occurs- a loss of electrons
