Water makes use of the hydrogen bond, a type of intermolecular force experienced when hydrogen is attracted to the electronegative atoms nitrogen, oxygen, or fluorine. Hydrogen bonding is the strongest intermolecular force. Water is a great solvent for hydrophilic molecules but hydrophobic molecules are, by definition, not easily disturbed by water.
This makes a clear exception to the "Universal Solvent" idea. I haven't read any literature claiming it to actually be the best solvent, but it does work well in many chemical situations. Water is a good solvent for polar compounds [citation needed] , and the reasons for this are laid out pretty well by John Snow, but that's not really what makes it the universal solvent. There's a lot of water [citation needed].
It literally falls from the sky. This means that for most applications, it's the absolutely cheapest solvent available. Water is a reasonably stable molecule. Few things you can dissolve in water are expected to react significantly with it. It won't readily burn or combust, even in vapour form, and its high heat capacity and prevalence see above means that it can effectively douse most runaway reactions that might occur, such as fires there are times when adding water to a fire is a bad idea, especially perhaps in a lab, but even those times the problem can be solved by adding a lot of water.
Unlike some other common solvents, water is not toxic [citation needed] , and is not a bio- or eco-hazard. This means that unused solvent can be disposed of without special precautions, and if the solute can be disposed of trivially, the solvent can as well. Water is everywhere [citation needed] , giving it another unique property: Unlike many other solvents, water won't absorb atmospheric water vapour, decreasing its purity as a matter of course. It'll still exchange water with the atmospheric vapour, of course, but it doesn't significantly change its make-up.
Water molecules will also not spontaneously decompose under most sane conditions. Furthermore, while the liquid phase is available at a wide range of temperatures, the solid and gaseous states are not out of reach when using even extremely basic equipment.
Water isn't always the best tool for the job, but it's almost always a good or great one, at least when working with polar compounds. A common alternative to water is ethyl alcohol, which has similar polar properties and operating temperatures, but ethanol does have weaknesses in the other categories mentioned here, i.
Consider a solvent miscibility table like the one linked. What is the least miscibile solvent? Water is the worst solvent.
Water is immiscible with 17 out of 30 of the other listed solvents. Why is water such a bad solvent? Hydrogen bonds. Water molecules are strongly hydrogen bonded to other water molucules. To dissolve something else, these hydrogen bonds need to be broken. For another prespective, look across the periodic table.
What does water stably dissolve? Does water dissolve gold, silver, copper, tin, lead, aluminum, and many other metals and metaloids like antimony, silicon, and germanium, as mercury does? There is nothing universal about water, except that there is a lot of it on Earth and we need it to live. Since water is polar as you note, and "like dissolves like" remains a good principle, I think the answer is that lots and lots of substances are polar. Most ionic salts are, for example.
Even substances that are polar covalent are at least slightly polar and so somewhat soluble and with agitation, more soluble. So you have to be really non-polar e. If we think of a lemonade, three ingredients are needed, water, lemons and sugar. By adding sugar it dissolves easily in lemonade, which is a drink that uses water as a base. An example as simple as that of lemonade serves to demonstrate the properties of water in action.
He Water is known as"the universal solvent"par excellence. However, although water is the most well-known solvent and one of the most important, it is not the only solvent used in the chemical industry. A solvent is simply a substance that can dissolve other molecules and compounds which are known as solutes. A homogeneous mixture of a solvent with a solute is known as a solution.
A solvent is always in the liquid state while a solute may be present in the solid, liquid or gaseous state. Examples of solvents are water, tiner, alcohol, milk. Examples of solutes are sugar, salt, acetic acid. Note that areas of highest salinity occur in regions of highest net evaporation, as one might expect. All other dissolved substances in seawater are at very low concentrations part per million or billion ppm or ppb; 10 -6 to 10 This Includes important nutrients such as phosphate and nitrate that are cycled by organisms elements called "bio-limiting" and essential for life.
Many metals have trace concentrations wanna' get rich? There are about 9 million tons of gold dissolved in seawater, which is about equal to all the gold mined on earth throughout history. As previously indicated, evaporation of seawater produces a predictable sequence of mineral salts minerals become saturated at a certain point. There is enough salt in the ocean to cover land with a layer m thick.
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