1. C6d Chemistry of Sodium Chloride (NaCl)
What is sodium chloride used for?
Sodium chloride is used to make:
1. chlorine –
2. sodium hydroxide -
3. hydrogen -
Note: To make household bleach _____________ and ________ are reacted together
We can see from the uses above that sodium chloride is an important raw material in
the chemical industry.
Where does sodium chloride (NaCl) come from?
Sodium Chloride is present in the Earth as ________________
In England it is found in Cheshire and extracted from the rocks by _________________.
1.
2.
3.
DISADVANTAGE – removing large amounts of salt from the rock can cause the Earth above to
collapse. This leads to cracks in houses and large holes appearing in roads and gardens. It is
called subsidence.
2. Electrolysis of a Sodium Chloride Solution (Brine)
power pack
Products: ___________ gas – bleaches moist litmus paper
____________ gas – lighted splint makes a squeaky pop
________________ – universal indicator turns blue/purple
Cathode ( - electrode) - hydrogen
Higher
Anode ( + electrode) - chlorine
Higher
Higher The ions that are left in solution are ___ and ____which together make NaOH,
sodium hydroxide. This is a strong alkali and turns universal indicator _______.
Foundation
brine molten sodium chloride
(sodium chloride solution)
Electrolysis Products
3. Higher Only
These are the products when brine is electrolysed and brine is a very concentrated
solution of sodium chloride. But what happens if we electrolyse a dilute solution or molten
sodium chloride?
1. Electrolysing dilute solutions of sodium chloride
If we electrolyse a much more dilute solution the anode produces _________ instead of
chlorine.
2. Electrolysing molten sodium chloride (not dissolved in water)
The products of electrolysis of molten sodium chloride are sodium and chlorine
cathode (-)
anode (+)
