Search results
Results from the WOW.Com Content Network
Pepper is sprinkled onto the surface of the water in the left dish; when a droplet of soap is added to that water, the specks of pepper move rapidly outwards. The Marangoni effect (also called the Gibbs–Marangoni effect ) is the mass transfer along an interface between two phases due to a gradient of the surface tension .
Persicaria hydropiper (syn. Polygonum hydropiper), also known as water pepper, marshpepper knotweed, arse smart [2] or tade, is a plant of the family Polygonaceae. A widespread species, Persicaria hydropiper is found in Australia, New Zealand, temperate Asia, Europe and North America.
Addition of sodium chloride reduces the solubility of the soap salts. The soaps precipitate due to a combination of common-ion effect and increased ionic strength . Sea, brackish and other waters that contain appreciable amount of sodium ions (Na + ) interfere with the normal behavior of soap because of common-ion effect.
Example of saponification reaction of a triglyceride molecule (left) with potassium hydroxide (KOH) yielding glycerol (purple) and salts of fatty acids ().. Saponification value or saponification number (SV or SN) represents the number of milligrams of potassium hydroxide (KOH) or sodium hydroxide (NaOH) required to saponify one gram of fat under the conditions specified.
In the case of a thin oil film, a layer of oil sits on top of a layer of water. The oil may have an index of refraction near 1.5 and the water has an index of 1.33. As in the case of the soap bubble, the materials on either side of the oil film (air and water) both have refractive indices that are less than the index of the film.
Elephant's toothpaste is a foamy substance caused by the quick decomposition of hydrogen peroxide (H 2 O 2) using potassium iodide (KI) or yeast and warm water as a catalyst. [1] How rapidly the reaction proceeds will depend on the concentration of hydrogen peroxide.
An example water jar puzzle. The water jar test, first described in Abraham S. Luchins' 1942 classic experiment, [1] is a commonly cited example of an Einstellung situation. . The experiment's participants were given the following problem: there are 3 water jars, each with the capacity to hold a different, fixed amount of water; the subject must figure out how to measure a certain amount of ...
Kettlewell's experiment was a biological experiment in the mid-1950s to study the evolutionary mechanism of industrial melanism in the peppered moth (Biston betularia). [ 1 ] [ 2 ] It was executed by Bernard Kettlewell , working as a research fellow in the Department of Zoology, University of Oxford .