Search results
Results From The WOW.Com Content Network
The aqueous solution in the classical reaction contains glucose, sodium hydroxide and methylene blue. [14] In the first step an acyloin of glucose is formed. The next step is a redox reaction of the acyloin with methylene blue in which the glucose is oxidized to diketone in alkaline solution [6] and methylene blue is reduced to colorless leucomethylene blue.
The expansion of the mixture is the result of vaporization of water and CO 2 inside the container. The gases inflate the mixture to form a snake-like shape, and give off a burned sugar smell. [1] The granularity of the sugar can greatly affect the reaction: powdered sugar reacts very quickly but sugar cubes take longer to react. [2]
The percentage is a mass concentration, so a 5% glucose/dextrose solution contains 50 g/L of glucose/dextrose (5 g per 100 ml). This usage is imprecise but widely used, as discussed at Mass concentration (chemistry) § Usage in biology. Glucose provides energy 4 kcal/gram, so a 5% glucose solution provides 0.2 kcal/ml.
A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules, and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. [2]
Pencil drawings were not known before the 17th century, [1] with the modern concept of pencil drawings taking shape in the 18th and 19th centuries. [1] Pencil drawings succeeded the older metalpoint drawing stylus, which used metal instead of graphite. [1] Modern artists continue to use the graphite pencil for artworks and sketches. [1]
A superscript attached to the ∞ symbol for a property of a solution denotes the property in the limit of infinite dilution." [1] One important parameter of a solution is the concentration, which is a measure of the amount of solute in a given amount of solution or solvent. The term "aqueous solution" is used when one of the solvents is water. [2]
Benedict's reagent (often called Benedict's qualitative solution or Benedict's solution) is a chemical reagent and complex mixture of sodium carbonate, sodium citrate, and copper(II) sulfate pentahydrate. [1] It is often used in place of Fehling's solution to detect the presence of reducing sugars and other reducing substances. [2]
For example, milk sugar (lactose) is a disaccharide made by condensation of one molecule of each of the monosaccharides glucose and galactose, whereas the disaccharide sucrose in sugar cane and sugar beet, is a condensation product of glucose and fructose. Maltose, another common disaccharide, is condensed from two glucose molecules. [7]