Lipids dissolve in non-polar solvents such as chloroform, benzene and diethyl ether. They do not dissolve in polar solvents such as water. The only exceptions to this rule are the phospholipids, which will partially dissolve in water.Know More
Phospholipids are partially soluble in polar solutions such as water because of the phosphate group at the molecule's head. This phosphate group is polar, and that portion will dissolve in water while the non-polar tail remains insoluble. Phospholipids' partial solubility is integral to their function as cell membranes.
The most common lipids found in nature are the triglycerides. Animal fats and vegetable oils are primarily composed of triglycerides, which may be either saturated or unsaturated. Saturated fats are solid at room temperature and occur most often in animal fat. Unsaturated fats are more common in vegetable oils and are liquid at room temperature.
Steroids are the third type of lipid. Steroids are ring-shaped lipids used in cell membranes and as hormones within the body. Cholesterol is the most common steroid hormone; other common steroid hormones found in humans are estrogen, testosterone, progesterone, cortisol and bile salts. Steroids do not share many physical or chemical properties with other lipids. Their insolubility in water is their primary similarity.Learn more about Solutions & Mixtures
Ionic compounds dissolve in water because the hydrogen and oxygen atoms in the H2O molecules have partial charges that attract the ions in the solid compound, causing it to dissociate into separated ions. Differences in electronegativity account for the partial positive charge carried by water's hydrogen atoms and the partial negative charge of its oxygen atoms. What is happening to the ionic compound when it dissolves is a separation of its ions from their preexisting solid crystal lattice structure into unattached ions that are free to move about in the solution.Full Answer >
Substances that have ionic molecules or polar molecules generally dissolve in water because water molecules have the ability to surround the those molecules completely and disperse them in solution. Non-polar molecules do not interact with water molecules and are therefore insoluble in water.Full Answer >
The Department of Physics at the University of Illinois states that sugar dissolves faster in hot water than in cold water because hot water gives sugar crystals energy. The hotter the water, the higher the energy, and the faster sugar crystals dissolve.Full Answer >
Salt does dissolve in water. Salt, chemically called sodium chloride, is made up of ionic bonds between sodium and chlorine ions. In a polar solvent such as water, the ions dissociate from one another and become surrounded by the water molecules.Full Answer >