What Dissolves Salt Besides Water?

With a polarity index of 9 or more, water is the only solution that can dissolve a salt.
••• Jupiterimages/Comstock/Getty Images

In order to dissolve a solid into a solution, molecular bonds must be broken. Sugars, which are molecular solids, have weak intermolecular forces binding them together. Salts, on the other hand, are ionic solids and have much stronger forces because of their polarized ions (magnets) which keep them together. It takes much more energy to pull apart salt molecules than it does sugar and keeping them apart requires substitution of molecules. Simply put, there are no other solutions besides water that will dissolve a salt.

Molecular Structure of Salts

A salt is called an ionic solid as outlined by the chemistry department at Purdue University in their explanation of solubility. Energy is needed in order to break the strong polar (magnetic) bonds and a substitute must replace the missing pieces in order to keep them separated. Water molecules separate the salt molecules and at the same time, the water molecules bond with the separated pieces in order to keep them apart. This process can only occur as long as there are water molecules. Once the solution reaches equilibrium (the water molecules have bonded with as many salt molecules as they can manage) the process stops. During the time that salt is dissolving in water, energy is high and the solution is highly conductive.

Solvents and the Polarity Index

Chemical-Ecology.net offers a list of solvents which shows water as having a polarity index of nine. That means that it is the most balanced solution with regard to its polarity, and, therefore, is the only solution which will dissolve a salt. Some salts are actually insoluble even in water. The New World Encyclopedia explains that like dissolves into like; basically, polar (magnetically charged) solids dissolve into polar solvents and non-polar (non-magnetically charged) solids dissolve into non-polar solvents. On the polarity index, the closest solvent to water in polarity is dimethyl sulfoxide at 7.2.

Soluble Salts

Salt is not just on your table.
••• Hemera Technologies/AbleStock.com/Getty Images

Table salt is just one type of salt and is water soluble. Other water-soluble salts include nitrates, chlorides, and sulfates. There are exceptions to the rule, though. A salt is considered insoluble if, by Purdue University’s definition, it can dissolve in room temperature water to a concentration of 0.1 moles per liter at the very least. InnovateUs.net offers that moles are the unit of measure of solubility of a substance and are calculated per liter.

Insoluble Salts

Some salts are insoluble. By Purdue University’s definition, a salt is considered insoluble is the aqueous (water) solution’s concentration at room temperature is not more than 0.001 moles at room temperature. The salts on this list include sulfides, oxides, hydroxides, chromates and phosphates. And, again, there are a few exceptions.

Related Articles

Rock Salt Vs. Table Salt to Melt Ice
Properties of Isopropyl Alcohol
Which Lipids Are Water Soluble?
Why Do Ionic Compounds Conduct Electricity in Water?
Why Does Sugar Affect the Freezing Point of Water?
A List of Three Properties of Ionic Compounds
Molecular Activity of Water Vs. Oil
What Happens to Ionic & Covalent Compounds When They...
Why Does Sugar Melt Ice?
How to Make Negatively Charged Water
Why Is Salt Water Heavier Than Tap Water?
In What Units Is Solubility Measured?
How is a Water Molecule Like a Magnet?
What Are the 5 Emergent Properties of Water?
Does Ice Melt Faster in Water or Soda?
How to Make a Supersaturated Solution
How Does Alcohol Dissolve Oil?
Defining Characteristics of Lipid Molecules
How to Calculate Cations & Anions

Dont Go!

We Have More Great Sciencing Articles!