CP – The behaviour of salty water Flashcards
What is the process of solar salt extraction?
- Water with a 3.5% salt conc. Sunlight/heat maks the water evaporate
- Precipitate of Calcium Carbonate (CaCO3) is formed.
- More evaporation = precipitation of Calcium sulphate (CaSO4)
- More evaporation = precipitation of Sodium Chloride (NaCl)
- Collect sodium chloride (table salt) for sale
What is the salt content of the sea?
~32-38ppt
What will happen if the concentration of a solution is increased by removing water?
Solution will become saturated.
Keep on removing water = solution becomes super saturated and precipitation will occur
What is true of sodium’s solubility?
Not very soluble – has a solid 3D orderly structure of atoms
What happens when temperature is increased for solutes like salt or sugar?
An increase in temperature means that the solution will hold more before becoming saturated
What does a polar substance dissolve in?
If a polar substance dissolves, it dissolves in polar solvents
What does a non-polar substance dissolve in?
If a nonpolar substance dissolves, it dissolves in nonpolar solvents
What is true of hydroxide (OH-) solubility?
Most hydroxides are only slightly soluble
Except Li+, Na+, K+ and NH4+
What is true of group 1 salts solubility?
Li+, Na+, K+, Cs+, Rb+ are soluble
Whats true of sulphate solubility?
Most sulphates are soluble
Except Ba2+, Ca2+, Pb2+, Ag+, Sr2+
What happens at equilibrium?
At equilibrium the forward and back reactions occur at the same rate
What is true of solubility products?
Solubility product is a constant and it is the equilibrium concentration of ions and salt multiplied together
What is true of silver nitrate’s and silver chloride’s solubility?
Silver nitrate is very soluble but silver chloride is not
What happens to silver chloride is silver nitrate is added to seawater?
Silver chloride precipitates
What can silver chloride precipitation when silver nitrate is added to seawater do?
It is used to determine chlorinate and therefore salinity
