Electrolysis Flashcards
What are electrolytes?
Ionic compounds molten or dissolved in water
What is electrolysis?
Electrical energy from a direct current breaking down electrolytes free irons are attracted to opposite charged electrodes
What are the negative ions called in electrolysis?
Anions
What are the positive ions called in electrolysis?
Cations
What is the negative electrode called?
The cathode
What electrode are the anions attracted to?
The anode
What electrode are the cat ions attracted to?
The cathode
What is the positive electrode called?
The anode
What happens at the cathode?
Reduction
What happens at the anode?
Oxidation
Why do we use carbon for electrodes?
They have a high melting point and don’t react with the reactants or products of electrolysis
Why do we use carbon for electrodes?
They have a high melting point and don’t react with the reactants or products of electrolysis
What ions compete at the cathode during electrolysis of solutions?
Hydrogen ions and the positive ions (metal) from the compound
What two ions compete at the anode during electrolysis of solutions?
Hydroxide ions from the water and negative ions (non-metal) from the compound
When is a metal produced at the cathode instead of hydrogen?
If it is lower than hydrogen on the metal reactivity series
What are the only metals that can possibly be produced at the cathode during electrolysis of solutions?
Copper, silver and gold
What happens if hydrogen is more reactive than the metal in electrolysis of solutions?
Hydrogen is produced at the cathode
Oxygen is produced at the anode unless what?
Unless the hydro oxide is competing with halide ions (bromide, chloride and iodide)
What is the gas test for hydrogen?
A lighted splint goes out with a squeaky pop
What is the gas test for oxygen?
A glowing splint relights
What is the gas test for chlorine?
Damp blue litmus paper tons red and then is bleached white
What is the hazard of copper sulphate solution?
Skin irritation and serious eye irritation
How do we prevent the hazards of copper sulfate solution ?
Wear gloves and eye protection
What is the hazard of the DC electricity supply?
Electric shock
How do we prevent the hazard of the DC electricity supply?
We make sure the electrodes do not touch and we make sure electricity supply is switched off before handling apparatus
What is oxidation?
The loss of electrons
What is reduction?
The gain of electrons
What acronym can we use for oxidation and reduction?
Oil rig
What side of the half equation is the electrons on if it is oxidation?
The product side
What side of the equation are the electrons if it is reduction
The left side
