When the attractive forces of the water molecules for the glucose exceeds the attractive forces between the glucose and its neighboring glucose molecules, the water can pull the sugar molecule out of the crystal. It is said that water has "dissolved" the sugar molecule. For example: water is polar, oil is non-polar. Water will not dissolve oil.
Water is polar, and table salt NaCl is ionic, which is extremely polar. According to the rule of thumb, like dissolves like, and polar dissolves polar; thus, water dissolves table salt.
Polar water molecules are attracted to ions atoms or groups of atoms with a charge where "cations" are ions with a positive charge and "anions" have a negative charge. Most ionic compounds have high solubility in water, which means that large concentrations of those compounds can dissolve before the capacity for water molecules to isolate the ions is exceeded. As a sign of mercy in its creation, seawater is electrically neutral; otherwise, the flow of current from the sea would be shocking!
All other dissolved substances in seawater are at very low concentrations parts per million or billion, ppm or ppb: to This includes important nutrients such as phosphate and nitrate that are cycled by organisms ions called "bio-limiting" and essential for life.
Metals are also found in trace concentrations. There are about 9 million tons of gold dissolved in seawater, which is about equal to all the gold mined on earth throughout history. Such natural deposits from ancient oceans are called "evaporites. Even though most ionic compounds are highly soluble in water, there are some that are insoluble or very slightly soluble.
Soluble substances can form a solution of at least 0. As an example, the LE of calcium carbonate CaCO3, or calcite , which is insoluble in water, is so large, a great amount of free energy would be required to break the strongly attracted ions apart, and this energy has to come from the enthalpy of hydration. However, the enthalpy of hydration is not large enough to overcome the large lattice energy, hence it does not dissolve in water and exists as a solid a precipitate form.
It would be very hard to predict whether a precipitate is formed in an aqueous reaction if there were not a number of patterns in the data obtained from measuring the solubility of various salts. These patterns form the basis for the solubility rules 7 which can guide predictions of whether a salt will dissolve in water. This sense of order and harmony in creation is an exceptional gift to human beings, for it makes our lives much easier.
Search Search. Filter by type:. Jun 15, Polar solvents dissolve polar solutes Confused yet? Related questions What factors affect solubility in a solid-liquid combination? What factors affect solubility in water? What factors affect solubility of ionic compounds?
What factors affect the solubility of gases in liquids? What factors affect the solubility of a solid? Liquid solvents are normally either polar or non-polar but, at high temperatures, liquid salts and metals can act as solvents.
We will limit ourselves to polar or non-polar solvents, marked in red in the above table, as they are the most common solvents. Dipoles Molecules are made of atoms that have bonded together in set patterns. Depending on how the atoms are arranged in the molecule, the molecule itself can sometimes have different charges on each end of the molecule thus forming a dipole.
Such molecules are said to be "polar", while molecules with no or little charge separation are called "non-polar" molecules. Polar molecules are aggressively attracted to other polar molecules, or even free ions, and form strong bonds between themselves. They feel little attraction to non-polar molecules and tend to ignore them in their rush to find other polar molecules or ions.
Non-polar molecules tend to group together, because they are pushed out of the way by polar molecules, forming weak bonds between themselves. In this way, polar molecules aggressively seek each other out, excluding non-polar molecules from mixing with them and forming a solution. While non-polar molecules form much weaker attractions for each other, they will mix and form solutions. Like dissolves like! Polar solvents Water is the most common polar solvent on Earth.
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