how much sodium hydroxide in grams must be added to seawater to precipitate 86.9mg of magnesium present?
There is not a lot of difference. They are both powerful bases but potassium hydroxide is more expensive. Sodium hydroxide is manufacture by electrolysis of seawater. Potassium Hydroxide just does not have a cheap source of raw material as seawater!
Most metals are not in any economic concentrations in seawater. The only exceptions are sodium and magnesium. A company did start up trying to extract lithium from seawater but it went bust but the technology will certainly be looked at again when lithium is needed in large amounts for making batteries. Bioengineering technology may be used in the future to get bacteria and algae to concentrate metals from seawater.
Magnesium is an essential element in your diet. Green spinach and many other green vegetables are useful sources.answer 2 Magnesium is commonly extracted from sea water, and for this purpose, you need warm sea water [for economics] and a plentiful supply of sea shells or other calcium source such as limestone. It is prepared using a flux electrolytic process in a similar manner to that for aluminium. Dolomite rock is another commercial source for this useful metal.
The density of seawater increases if salinity increases.
97% seawater, other 3% is freshwater.
Magnesium chloride is soluble in water.
precipitate out the solution
It should say, "Magnesium and CHLORINE make up most of the ions in seawater." Not chloride.
First, the sea water is collected in large basins and heated to evaporate some of the water. This yields a concentrated solution of water and various salts which are mixed with calcium hydroxide (lime) to yield a magnesium hydroxide precipitate. The precipitate is then reacted with hydrochloric acid to yield magnesium chloride. This is then separated into molten magnesium metal and chlorine gas ions through the electrolysis process. The chlorine is reacted with hydrogen to yield hydrochloric acid to be recycled, while the molten magnesium is then cast into ingots.
because it just is :D
They take magnesium.
When fresh water is removed from ocean water, the salts that are left behind are also a valuable resource. Over half of the world's supply of magnesium, a strong, light metal, is obtained from seawater in this way.
The four MAIN IONS in seawater in descending order of abundance are: CI: Chloride Na: Sodium SO4: Sulfate Mg: magnesium Found in Leckie-Yuretich: Investigating the Ocean, Page 114, Seawater Salinity: The salt of the Ocean
Magnesium can be extracted from the minerals Dolomite (CaCO3·MgCO3) and Carnallite (KCl·MgCl2·6H2O), but is most often obtained from seawater
Sodium chloride, potassium chloride, magnesium chloride
It's an actual, and common, compound - MgCl2 (magnesium chloride), a constituent of seawater, has many uses including just chasing off the chlorine atoms to recover the magnesium metal.