in the process of separating salt and water, why does the mass of the salt increase after the evaporation?
827509
Salt is a crystal......crystals grow when brought back to solid form
242761
allow the salt-water to evaporate (in a hot container), then catch the water vapour and allow it to condense in/on a cold container.
242447
place the mixture in water. salt would be dissolved. to recover the salt evaporate the water.
739985
the water is relesed as vapor from the liquid when the liquid is heated. Water changes phase and becomes gas, its called evaporation.
49972
As water flows in rivers, it picks up small amounts of mineral salts from the rocks and soil of the river beds. This very-slightly salty water flows into the oceans and seas. The water in the oceans only leaves by evaporating (and the freezing of polar ice), but the salt remains dissolved in the ocean - it does not evaporate. So the remaining water gets saltier and saltier as time passes.
826959
The basic answer to that is:\nAs water falls on land and runs into the oceans it picks up minerals.\nWhen it gets to the ocean the minerals get mixed into the ocean water.\nSunlight causes the water to evaporate but leaves the minerals behind.\nThe water then falls on land again repeating the process.\nEventually the salt content in the oceans built up to where it is today. And continues to build up.
90693
At the moment, they are in balance.  The salt in the ocean came from minerals and rocks dissolved over millions of years. To markedly increase salinity in the world's ocean, a substantial quantity of water would have to be lost. In general, our planet biosphere has a set quantity of water. It is either tied up in oceans, living creatures, clouds/vapor, ice or the freshwater sources in wells, rivers, etc. What evaporates from the sea is ultimately returned via rivers, runoff, etc. The melting icecaps is actually a SUBSTANTIAL contributer to the total volume of the seas. However, as sea levels rise, so does rthe capacity to absorb more minerals, so the salinity would fluctuate over a few thousand years and stabilize about where it is now.
131636
In pretty much all substances, when you heat something (assuming no phase change), the material becomes less dense due to the fact that its volume expands and mass stays constant.\n\nSo if you were to heat a pot of water for example from the bottom on a convection stove, the hot water at the bottom would become less dense than the cooler water on top.  The hot water would rise and it is rises, the cooler water sinks down to take its place.
819026
Because of the sea salt.
864865
'Heating to constant mass' meaning to heat a substance (usually a powder or crystals) until the mass of the substance remains constant/the same. this is done in quanatative chemistry when the mass is weighed, then heated and measured again after 5-10mins and repeated until the mass doesn't change.\n\nthis is important because the mass of the solute needs to be known. but usually there are molecules of water trapped within  it and the exact mass isn't known. so by doing this, the water molecules evaporate and what is left behind is the salt itself. so this is done to find out the actual mass of the substance.\n\nhope ths helps
444550
The difference in solubility of the components allows for separation.  I don't remember the specifics, but that is the reason.  Water will not have a big enough difference.
737067
Evaporation.\n\nSalt water + heat source + vessel. Apply heat source to vessel containing salt water. Evaporate water. Harvest salt.
554126
because of the salt content, salt tends to draw water out, hence out in the open the salt would allow the water to be evaporated much more quickly than fresh water
945741
Due to the fact that this salt is found as a hydrated salt (first Na2SO4.10H20 and then as Na2SO4.7H2O, so, with the increase of temperature it looses moisture (water)). When the Na2SO4.10H2O is heated the solution of this compound decreases because a solid phase and a liquid phase are formed after the initial heating.
552084
I assume this is based on the principle of Osmosis. I would like a bit more data before answering further.
209819
Add water to dissolve the salt.  Drain water and boil off.  Salt is now separated from sand.
570839
Salt only holds water. The volume of the other stuff contribute as well.  If you eat a ton of frys or eat only 1 ice cream, the frys will add more weight than the 1 ice cream.