You need to monitor the solution to see when the crystals start gathering at the bottom of the solution. You can slowly add alum until it stops dissolving. The point just before it starts its sedimentation at the bottom is the point when the solution is saturated.
Answer:
the water which are very healthy is known as hydrated water
I would pick "<span>Unsaturated hydrocarbons are very reactive." This is because while unsaturated hydrocarbons are indeed more reactive than their saturated counterparts, they still do require some energy, called activation energy, to be overcome before the reactions occur.</span>