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Substances That Won't Dissolve in Water

Water has many uses, because several substances dissolve into it. The reason why water can clean up dirt effectively is that the dirt dissolves gradually into the water. Solubility is not only influenced by the specific compound, but also by the temperature and pressure. Some substances completely mix into water, such as ethanol, while other substances only dissolve into water somewhat, such as silver chloride. However, people may notice they cannot clean up oil and other substances with water. Not all substances dissolve, due to fundamental subatomic properties.

Cations and Anions
- Water molecules are made of two hydrogen and one oxygen atom. Oxygen attracts the electrons more than hydrogen, giving it a somewhat negative charge and giving the hydrogen a positive charge. These charges draw atoms to them, breaking the atoms into individual cations and anions, which are both ions. Cations hold positive charges and anions hold negative charges.
Methane
- Water is a solvent that mixes well with other substances. Substances that dissolve in water can be solids, liquids or gases. However, some substances do not dissolve at all in water and are called ̶0;insoluble̶1; substances. Methane does not dissolve in water, since the methane atoms would have to move between the water molecules and break the hydrogen bonds, which requires too much energy.
Oil
- Chemical polarity is a concept where there is a separation of electrical charges caused by an uneven sharing of electrons. Polar chemicals are attracted to each other. Nonpolar chemicals share electrons uniformly and are thus not attracted to polar chemicals.
  
  Water and oil do not mix, since they have different levels of density, so the oil floats to the top of the water. Oil also doesn̵7;t mix with water because it is nonpolar, so it does not interact well with the water molecules. Though oil is a substance that is not soluble in water, it does dissolve in organic solvents.
Insoluble Vitamins
- Vitamins benefit the body, but consuming vitamins in excessive quantities can cause health problems. Some vitamins in the body are insoluble. Since the body uses water to eliminate vitamins from the body when it has too many, insoluble vitamins are harder to eliminate and pose a greater toxicity threat. Vitamins A, D and E are not water soluble, but do dissolve in fats.
Covalent Compounds
- Covalent compounds share electrons, instead of transferring electrons between each other, according to Elmhurst University. The covalent compounds form most often when two nonmetals bond to each other. Covalent compounds usually aren̵7;t dissolved in water, since they are nonpolar, while water is a polar solvent. Similar substances tend to dissolve into each other. Not all covalent compounds fail to dissolve in water.

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