electrolysis

What is electrolysis?

Using electricity to break down electrolytes to form elements

What can we electrolyse?

• molten salts

• Solutions

What are electrolytes?

Ionic compounds that are either molten or dissolved in water

Electrolysis is a process where electrical energy, from a ___1___ current supply breaks down ___2____ . The free moving _3_ in electrolytes are attracted to the oppositely charged ____4____ which connect to the dc supply.

1= direct

2= electrolytes

3= ions

4= electrodes

Cathode

Negatively charged electrodes, positively charged ions move towards the cathode.

Cations

Positively charged ions

Anode

Positively charged electrode, negatively charged ions move towards the anode.

During the electrolysis of molten salts, what is formed at the anode and cathode?

At the anode = non metal

At the cathode = Metal

The general products of electrolysis

• positive ions gain electrons from the negatively charged cathode

• Negative ions lose electrons at the positively charged anode

Negative Metal ions

anions

What would be the products of the electrolysis of molten calcium chloride?

• positively charged calcium ions move to the negative electrode

• Negatively charged chloride ions move to the positive electrode

• The atoms join up in pairs to form Cl2 (chlorine gas) which is formed at the anode