What is meant by electrolysis ? | Electrolysis is the breakdown of an ionic compound when molten or in aqueous solution using electricity |
What is an electrolyte? | The liquid which conducts electricity in electrolysis |
What are electrodes used for? | They are used bring electricity in and out an electrolyte during electrolysis. |
What are anodes, and what type of ions do they attract ? | The are positive electrodes which attract negative ions(Anions) |
What are cathodes, and what type of ions do they attract? | They are positive electrodes which attract positive ions(Cations) |
Name two elements which could be used to make inert electrodes. | Graphite and platinum |
What is the rule used to decide if a metal or hydrogen forms at cathode when its a solution? | IF the metal is more reactive than hydrogen, hydrogen form at the cathode IF hydrogen is more reactive then metal forms at the cathode. |
What is the rule used to decide if a another non-metal or oxygen forms at the anode when its a solution? | If it is concentrated solution of halide then halide forms at the anode but if its a dilute solution or no halide then oxygen forms at the anode |
What kind of reaction takes place in the anode? | Oxidation(since they lose electrons) |
What kind of reaction takes place in the cathode? | Reduction(sine they gain electrons) |
In overall what kind reaction is electrolysis? | A redox reaction |
What is brine ? | A concentrated solution of sodium chloride. |
What chemicals can be obtained through the electrolysis of brine? | Sodium hydroxide, Chlorine, Hydrogen |
Name three uses of Chlorine | Used for sterilizing
Used to produce hydrochloric acid and hydrogen chloride
Used for making plastic PVC |
Name three uses of Sodium Hydroxide. | Soaps
Detergent
Medical drugs |
Name three uses of Hydrogen | Used to make hydrogen peroxide
Used as fuel in hydrogen fuel cells
Used to make nylon |
Give two uses of electrolysis excluding decomposition | Refining(purifying)
Electroplating |
How can you purify copper using electrolysis? | The anode should be the impure copper and the cathode should be pure copper.
The copper in the anode dissolves but the impurity does not they just drop to the floor
A layer of the pure copper builds up on the cathode |
Give two reasons for why electroplating is used | Used to make another metal look better
Used to prevent corrosion |
How can you electroplate a steel jar using electroplating? | The anode should be made of silver and the steel jar should be the cathode
The silver from anode dissolves to form positive ions in silver nitrate solution
The silver ions are attracted to the cathode where they form a layer of silver on the steel jar |