Electrolysis

Question 1

What is electrolysis?

Answer 1

the process of breaking down an ionic substance using an electric current

Question 2

Which compounds will undergo electrolysis and why?

Answer 2

ionic -> contain charged ions which are free to move in molten/liquid solutions

Question 3

what will be made at the anode and cathode in electrolysis of a solution?

Answer 3

• least reactive substance made
• anode (+), halogen (Cl2, Br2, I2) or O2
• cathode (-), H2, Cu, Ag, Au, Pt

Question 4

what is the 1/2 equation for oxygen?

Answer 4

4OH^- -> O2 + 2H2O + 4e^-

Question 5

in electroplating what are the anode and cathode made of?

and what is the electolite?

Answer 5

anode->plating material
cathode -> object to be plated
Electrolyte -> solution of anode

Question 6

why do we electro plate things?

Answer 6

• more attractive
• protection from corrosion
• save money
• increase hardness

Question 7

what is sodium chloride made up of?

Answer 7

chlorine, hydrogen, sodium hydroxide (bleach anad HCl)

Question 8

what can be made from chlorine

. . . .. . . . . ……………………. hydrogen

Answer 8

Chlorine - bleach, hydrochloric acide

hydrogen - hydrochloric acid

Question 9

what is the use of chlorine?

Answer 9

drugs, sterilise water (kills bacteria)

Question 10

what is the use of bleach?

Answer 10

water treatment

Question 11

what is the use of hydrochloric acid?

Answer 11

water treatment, cleaning products

Question 12

what is the use of hydrogen?

Answer 12

margarine

Question 13

what is the use of sodium hydroxide?

Answer 13

water treatment, purify petrol and gas