Search results
Results from the WOW.Com Content Network
Valine (symbol Val or V) [4] is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH 3 + form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO − form under biological conditions), and a side chain isopropyl group, making it a non-polar aliphatic amino acid.
Polar liquids have a tendency to be more viscous than nonpolar liquids. [citation needed] For example, nonpolar hexane is much less viscous than polar water. However, molecule size is a much stronger factor on viscosity than polarity, where compounds with larger molecules are more viscous than compounds with smaller molecules.
Low-temperature ionic liquids (below 130 K) have been proposed as the fluid base for an extremely large diameter spinning liquid-mirror telescope to be based on the Moon. [25] Water is a common impurity in ionic liquids, as it can be absorbed from the atmosphere and influences the transport properties of RTILs, even at relatively low ...
A typical wetting solution molecule consists of a hydrophilic head and long hydrophobic tail. (From top to bottom: non-ionic, anionic, cationic and zwitterionic.) Wetting solutions are liquids containing active chemical compounds that minimise the distance between two immiscible phases by lowering the surface tension to induce
The hydrophobic effect is the desire for non-polar molecules to aggregate in aqueous solutions in order to separate from water. [22] This phenomenon leads to minimum exposed surface area of non-polar molecules to the polar water molecules (typically spherical droplets), and is commonly used in biochemistry to study protein folding and other ...
Another example is soap, which has a hydrophilic head and a hydrophobic tail, allowing it to dissolve in both water and oil. Hydrophilic and hydrophobic molecules are also known as polar molecules and nonpolar molecules, respectively. Some hydrophilic substances do not dissolve. This type of mixture is called a colloid.
The hydrophobic effect depends on the temperature, which leads to "cold denaturation" of proteins. [19] The hydrophobic effect can be calculated by comparing the free energy of solvation with bulk water. In this way, the hydrophobic effect not only can be localized but also decomposed into enthalpic and entropic contributions. [3]
The hydrophobic interaction is mostly an entropic effect originating from the disruption of the highly dynamic hydrogen bonds between molecules of liquid water by the nonpolar solute, causing the water to form a clathrate-like structure around the non-polar molecules.