C3.4.

Question 1

What must be needed for electrolysis,, how do you do it?

What happens when discharge

What are inert electrodes

Answer 1

A process where a current is passed through a compound, causing a chemical change

1) electrolyte (dissolved ionic compound now has mobile and can conduct electricity)
2) two electrodes, negative cathod, positive anode
3) electrical power supply

When ions become atoms or molecules they have DISCHARGED

2) not changed by electrolysis , jnreavtive like copper, used for electrolysis of aqueous or liquid state

Question 2

WHAT IS FORMULA FOR DISCHARGE IF H+ AND OH-

IMPORTSNT

Answer 2

2H+ + 2e-= h2 (book says 4?)

4OH- = 2h2o + o2 +4e-

Question 3

ELECTROPLATING

Answer 3

metal ions from the electrolyte are discharged onto the cathode, the THING YOU want TO PLATE.

Silver atoms are lost at anode and gained at cathode , move through electrolyte.

The electrolyte should contain the material ions, silver nitrate

Must be non inert, so they can affect

Question 4

Okay so how does copper purification work

Answer 4

Copper electrodes are non inert
Two copper electrodes, the copper will be remeoved from the anode, and given to the cathode.
The circuit takes electrons from the anode and give it to the ions in the ecktet ode.

Make sure the electrolyte is copper related so only copper ions go through.

At the anode, cu= cu2+ 2e-
At the cathode cu2+ +2e-= cu

Basically once ion solution gone the copper dissolved and become Dixon’s as it becomes aqueous

Question 5

He’s ‘‘tis Lordy dc st each electrode snd why?

Answer 5

The least reactive thing, so at cathode is reactivity scale, anode is n97oncs, where the (more reactive leftest one is produced)

Question 6

What happens to the thingd left behind?

Answer 6

They can sometimes join to form a whole new compound

Question 7

Electroplating notes

How is copper predicted then?
Thing to remember

Answer 7

Electroplating is the process of using a metal to coat another metal.

The electrodes used are not inert, meaning they can change during electrolysis (vital for electroplating)

The cathode is typically the metal you want to be coated, and anode the metal that coats.

Then the electrolyte must be something that is soluble in water and contains ions of the metal you want to coat (such as silver nitrate)

Basically what happens is ions from electrolyte are discharged on the surface of the ctahode, snd these are being replaced by atoms becoming ions by LOSING electrons at the anode. Overall ions move from the anode to cathode through electrolyte, depositing here, until all the atoms in anode are used.

The object must be at the cathode because if it was at anode it would lose electrons here, but where would these go? The whole reason it is a circuit is because electrons lost at positive anode move and are gained at negative cathode .

2) The copper want to be pruifed is placed at the cathode, and impure at anode. There is electorlhtebsolution cintsining copper too.
- at the anode, copper loses electrons to become copper ions, and electrons travel to cathode
- attracted to negative cathode, copper ions discharge and gain electrons to become copper ions, depositing as they go, and so this is reduction.
- here mass increases and mass decreases at inside where impurity’s collect at the bottom

3) that the other thing in the electrolyte solution is produced at anode, so based on this it is important to chose something as a result