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106-403: Molasses ( / m ə ˈ l æ s ɪ z , m oʊ -/ ) is a viscous byproduct, principally obtained from the refining of sugarcane or sugar beet juice into sugar . Molasses varies in the amount of sugar, the method of extraction and age of the plant. Sugarcane molasses is usually used to sweeten and flavour foods. Molasses is a major constituent of fine commercial brown sugar . Molasses

212-420: A fertilizer . Exaggerated health benefits claimed for blackstrap molasses were the theme of the 1951 novelty song Black Strap Molasses , recorded by Groucho Marx , Jimmy Durante , Jane Wyman and Danny Kaye . Unlike highly refined sugars, molasses contains significant amounts of vitamin B 6 and minerals , including calcium , magnesium , iron and manganese ; one tablespoon provides up to 20% of

318-423: A lilac color with a peak emission wavelength of 766.5 nanometers. Neutral potassium atoms have 19 electrons, one more than the configuration of the noble gas argon . Because of its low first ionization energy of 418.8   kJ/mol, the potassium atom is much more likely to lose the last electron and acquire a positive charge, although negatively charged alkalide K ions are not impossible. In contrast,

424-435: A magnetic field , possibly to the point of behaving like a solid. The viscous forces that arise during fluid flow are distinct from the elastic forces that occur in a solid in response to shear, compression, or extension stresses. While in the latter the stress is proportional to the amount of shear deformation, in a fluid it is proportional to the rate of deformation over time. For this reason, James Clerk Maxwell used

530-436: A constant viscosity ( non-Newtonian fluids ) cannot be described by a single number. Non-Newtonian fluids exhibit a variety of different correlations between shear stress and shear rate. One of the most common instruments for measuring kinematic viscosity is the glass capillary viscometer. In coating industries, viscosity may be measured with a cup in which the efflux time is measured. There are several sorts of cup—such as

636-506: A fluid, just as thermal conductivity characterizes heat transport, and (mass) diffusivity characterizes mass transport. This perspective is implicit in Newton's law of viscosity, τ = μ ( ∂ u / ∂ y ) {\displaystyle \tau =\mu (\partial u/\partial y)} , because the shear stress τ {\displaystyle \tau } has units equivalent to

742-400: A human body of 70 kg, about 4,400 nuclei of K decay per second. The activity of natural potassium is 31 Bq /g. Potash is primarily a mixture of potassium salts because plants have little or no sodium content, and the rest of a plant's major mineral content consists of calcium salts of relatively low solubility in water. While potash has been used since ancient times, its composition

848-415: A momentum flux , i.e., momentum per unit time per unit area. Thus, τ {\displaystyle \tau } can be interpreted as specifying the flow of momentum in the y {\displaystyle y} direction from one fluid layer to the next. Per Newton's law of viscosity, this momentum flow occurs across a velocity gradient, and the magnitude of the corresponding momentum flux

954-400: A plant salt, by a similar technique, demonstrating that the elements, and thus the salts, are different. Although the production of potassium and sodium metal should have shown that both are elements, it took some time before this view was universally accepted. Because of the sensitivity of potassium to water and air, air-free techniques are normally employed for handling the element. It

1060-852: A relatively stable natural shelf life. Poor flavour and the trace toxicity of low doses of sulfur dioxide are also factors that have led to its removal. Molasses is composed of 22% water, 75% carbohydrates and very small amounts (0.1%) of fat . It contains no protein . In a reference amount of 100 grams, molasses is a rich source (20% or more of the Daily Value , DV) of vitamin B6 and several dietary minerals , including manganese , magnesium , iron , potassium and calcium . The sugars in molasses are on average sucrose (39% of total carbohydrates), glucose (16%) and fructose (17%) (data from USDA nutrition table). The uses of molasses in food production may include: Viscosity Viscosity quantifies

1166-491: A second boiling and sugar extraction and has a slightly bitter taste. Boiling the sugar syrup a third time yields dark, viscous blackstrap molasses ( 'C' Molasses ), known for its robust flavour. During this process, the majority of sucrose from the original juice is crystallized and removed. The bitterness of blackstrap molasses is much greater than in the regular form of molasses. It is sometimes used in baking or to produce ethanol , as an ingredient in cattle feed , or as

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1272-416: A specific fluid state. To standardize comparisons among experiments and theoretical models, viscosity data is sometimes extrapolated to ideal limiting cases, such as the zero shear limit, or (for gases) the zero density limit. Transport theory provides an alternative interpretation of viscosity in terms of momentum transport: viscosity is the material property which characterizes momentum transport within

1378-486: A variety of graphite intercalation compounds , including KC 8 . There are 25 known isotopes of potassium, three of which occur naturally: K (93.3%), K (0.0117%), and K (6.7%) (by mole fraction). Naturally occurring K has a half-life of 1.250 × 10 years. It decays to stable Ar by electron capture or positron emission (11.2%) or to stable Ca by beta decay (88.8%). The decay of K to Ar

1484-477: A wide variety of proteins and enzymes. Potassium levels influence multiple physiological processes, including Potassium homeostasis denotes the maintenance of the total body potassium content, plasma potassium level, and the ratio of the intracellular to extracellular potassium concentrations within narrow limits, in the face of pulsatile intake (meals), obligatory renal excretion, and shifts between intracellular and extracellular compartments. Plasma potassium

1590-552: Is derived from the Dutch word for syrup, stroop . Sugar cane molasses is an ingredient used in baking and cooking. It was popular in the Americas before the 20th century, when it was plentiful and commonly used as a sweetener in foods and an ingredient in brewing beer in the colonies. George Washington had a notebook that contains a molasses beer recipe. To produce molasses, sugar cane is harvested and stripped of leaves. Its juice

1696-418: Is potassium cobaltinitrite , K 3 [Co(NO 2 ) 6 ] , which is used as artist's pigment under the name of Aureolin or Cobalt Yellow. The stable isotopes of potassium can be laser cooled and used to probe fundamental and technological problems in quantum physics . The two bosonic isotopes possess convenient Feshbach resonances to enable studies requiring tunable interactions, while K

1802-664: Is 1 cP divided by 1000 kg/m^3, close to the density of water. The kinematic viscosity of water at 20 °C is about 1 cSt. The most frequently used systems of US customary, or Imperial , units are the British Gravitational (BG) and English Engineering (EE). In the BG system, dynamic viscosity has units of pound -seconds per square foot (lb·s/ft ), and in the EE system it has units of pound-force -seconds per square foot (lbf·s/ft ). The pound and pound-force are equivalent;

1908-457: Is a linear combination of the shear and bulk viscosities that describes the reaction of a solid elastic material to elongation. It is widely used for characterizing polymers. In geology , earth materials that exhibit viscous deformation at least three orders of magnitude greater than their elastic deformation are sometimes called rheids . Viscosity is measured with various types of viscometers and rheometers . Close temperature control of

2014-469: Is a macronutrient required for life on Earth. K occurs in natural potassium (and thus in some commercial salt substitutes) in sufficient quantity that large bags of those substitutes can be used as a radioactive source for classroom demonstrations. K is the radioisotope with the largest abundance in the human body . In healthy animals and people, K represents the largest source of radioactivity, greater even than C . In

2120-493: Is a strong base . Illustrating its hydrophilic character, as much as 1.21 kg of KOH can dissolve in a single liter of water. Anhydrous KOH is rarely encountered. KOH reacts readily with carbon dioxide ( CO 2 ) to produce potassium carbonate ( K 2 CO 3 ), and in principle could be used to remove traces of the gas from air. Like the closely related sodium hydroxide , KOH reacts with fats to produce soaps . In general, potassium compounds are ionic and, owing to

2226-462: Is a calculation derived from tests performed on drilling fluid used in oil or gas well development. These calculations and tests help engineers develop and maintain the properties of the drilling fluid to the specifications required. Nanoviscosity (viscosity sensed by nanoprobes) can be measured by fluorescence correlation spectroscopy . The SI unit of dynamic viscosity is the newton -second per square meter (N·s/m ), also frequently expressed in

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2332-406: Is a main constituent of some varieties of baking powder ; it is also used in the silvering of mirrors. Potassium bromate ( KBrO 3 ) is a strong oxidizer (E924), used to improve dough strength and rise height. Potassium bisulfite ( KHSO 3 ) is used as a food preservative, for example in wine and beer -making (but not in meats). It is also used to bleach textiles and straw, and in

2438-454: Is a necessary element for plants and that most types of soil lack potassium caused a steep rise in demand for potassium salts. Wood-ash from fir trees was initially used as a potassium salt source for fertilizer, but, with the discovery in 1868 of mineral deposits containing potassium chloride near Staßfurt , Germany, the production of potassium-containing fertilizers began at an industrial scale. Other potash deposits were discovered, and by

2544-550: Is a viscosity tensor that maps the velocity gradient tensor ∂ v k / ∂ r ℓ {\displaystyle \partial v_{k}/\partial r_{\ell }} onto the viscous stress tensor τ i j {\displaystyle \tau _{ij}} . Since the indices in this expression can vary from 1 to 3, there are 81 "viscosity coefficients" μ i j k l {\displaystyle \mu _{ijkl}} in total. However, assuming that

2650-677: Is accelerated by minute amounts of transition metal salts. Because it can reduce the salts to the metal, potassium is often used as the reductant in the preparation of finely divided metals from their salts by the Rieke method . Illustrative is the preparation of magnesium: Potassium is formed in supernovae by nucleosynthesis from lighter atoms. Potassium is principally created in Type II supernovae via an explosive oxygen-burning process . These are nuclear fusion reactions, not to be confused with chemical burning of potassium in oxygen. K

2756-524: Is also formed in s-process nucleosynthesis and the neon burning process . Potassium is the 20th most abundant element in the solar system and the 17th most abundant element by weight in the Earth. It makes up about 2.6% of the weight of the Earth's crust and is the seventh most abundant element in the crust. The potassium concentration in seawater is 0.39   g/L (0.039 wt/v%), about one twenty-seventh

2862-448: Is also used in organic synthesis to make nitriles . Potassium carbonate ( K 2 CO 3 or potash) is used in the manufacture of glass, soap, color TV tubes, fluorescent lamps, textile dyes and pigments. Potassium permanganate ( KMnO 4 ) is an oxidizing, bleaching and purification substance and is used for production of saccharin . Potassium chlorate ( KClO 3 ) is added to matches and explosives. Potassium bromide (KBr)

2968-433: Is also used in some mines. The resulting sodium and magnesium waste is either stored underground or piled up in slag heaps . Most of the mined potassium mineral ends up as potassium chloride after processing. The mineral industry refers to potassium chloride either as potash, muriate of potash, or simply MOP. Pure potassium metal can be isolated by electrolysis of its hydroxide in a process that has changed little since it

3074-532: Is called the rate of shear deformation or shear velocity , and is the derivative of the fluid speed in the direction parallel to the normal vector of the plates (see illustrations to the right). If the velocity does not vary linearly with y {\displaystyle y} , then the appropriate generalization is: where τ = F / A {\displaystyle \tau =F/A} , and ∂ u / ∂ y {\displaystyle \partial u/\partial y}

3180-457: Is derived from the Latin viscum (" mistletoe "). Viscum also referred to a viscous glue derived from mistletoe berries. In materials science and engineering , there is often interest in understanding the forces or stresses involved in the deformation of a material. For instance, if the material were a simple spring, the answer would be given by Hooke's law , which says that

3286-448: Is determined by the viscosity. The analogy with heat and mass transfer can be made explicit. Just as heat flows from high temperature to low temperature and mass flows from high density to low density, momentum flows from high velocity to low velocity. These behaviors are all described by compact expressions, called constitutive relations , whose one-dimensional forms are given here: where ρ {\displaystyle \rho }

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3392-540: Is equal to the SI millipascal second (mPa·s). The SI unit of kinematic viscosity is square meter per second (m /s), whereas the CGS unit for kinematic viscosity is the stokes (St, or cm ·s = 0.0001 m ·s ), named after Sir George Gabriel Stokes . In U.S. usage, stoke is sometimes used as the singular form. The submultiple centistokes (cSt) is often used instead, 1 cSt = 1 mm ·s  = 10  m ·s . 1 cSt

3498-507: Is illustrative: The potassium cobaltinitrite is obtained as a yellow solid. Potassium ions are an essential component of plant nutrition and are found in most soil types. They are used as a fertilizer in agriculture , horticulture , and hydroponic culture in the form of chloride (KCl), sulfate ( K 2 SO 4 ), or nitrate ( KNO 3 ), representing the 'K' in 'NPK' . Agricultural fertilizers consume 95% of global potassium chemical production, and about 90% of this potassium

3604-576: Is in terms of the standard (scalar) viscosity μ {\displaystyle \mu } and the bulk viscosity κ {\displaystyle \kappa } such that α = κ − 2 3 μ {\displaystyle \alpha =\kappa -{\tfrac {2}{3}}\mu } and β = γ = μ {\displaystyle \beta =\gamma =\mu } . In vector notation this appears as: where δ {\displaystyle \mathbf {\delta } }

3710-406: Is limited in biotin (vitamin H or B 7 ) for cell growth and hence may be supplemented with a biotin source. The non-sugar content includes many salts, including calcium , potassium , oxalate and chloride . It contains betaine and the trisaccharide raffinose . These result from the concentration of the original plant material or other chemicals in processing and are unpalatable to humans. It

3816-583: Is mined in Canada , Russia , Belarus , Kazakhstan , Germany , Israel , the U.S., Jordan , and other places around the world. The first mined deposits were located near Staßfurt, Germany, but the deposits span from Great Britain over Germany into Poland. They are located in the Zechstein and were deposited in the Middle to Late Permian . The largest deposits ever found lie 1,000 meters (3,300 feet) below

3922-658: Is not a fundamental law of nature, but rather a constitutive equation (like Hooke's law , Fick's law , and Ohm's law ) which serves to define the viscosity μ {\displaystyle \mu } . Its form is motivated by experiments which show that for a wide range of fluids, μ {\displaystyle \mu } is independent of strain rate. Such fluids are called Newtonian . Gases , water , and many common liquids can be considered Newtonian in ordinary conditions and contexts. However, there are many non-Newtonian fluids that significantly deviate from this behavior. For example: Trouton 's ratio

4028-498: Is obtained from natural sources such as guano and evaporites or manufactured via the Haber process ; it is the oxidant in gunpowder ( black powder ) and an important agricultural fertilizer. Potassium cyanide (KCN) is used industrially to dissolve copper and precious metals, in particular silver and gold , by forming complexes . Its applications include gold mining , electroplating , and electroforming of these metals ; it

4134-401: Is one of only two stable fermions amongst the alkali metals. An alloy of sodium and potassium, NaK is a liquid used as a heat-transfer medium and a desiccant for producing dry and air-free solvents . It can also be used in reactive distillation . The ternary alloy of 12% Na, 47% K and 41% Cs has the lowest melting point of −78   °C of any metallic compound. Metallic potassium

4240-429: Is produced mostly by decomposition of the complex minerals kainite ( MgSO 4 ·KCl·3H 2 O ) and langbeinite ( MgSO 4 ·K 2 SO 4 ). Only a very few fertilizers contain potassium nitrate. In 2005, about 93% of world potassium production was consumed by the fertilizer industry. Furthermore, potassium can play a key role in nutrient cycling by controlling litter composition. Potassium citrate

4346-629: Is rich in vitamins and minerals, including vitamin B6 , iron , calcium , magnesium , and potassium . There are different types of molasses, including first molasses (highest sugar content), second molasses (slightly bitter), and blackstrap molasses (the darkest and most robust in flavor). Molasses was historically popular in the Americas before the 20th century as a sweetener. It is still commonly used in traditional cuisine, such as in Madeira Island 's traditional dishes. In addition to culinary uses, molasses has industrial applications, such as in

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4452-435: Is supplied as KCl. The potassium content of most plants ranges from 0.5% to 2% of the harvested weight of crops, conventionally expressed as amount of K 2 O . Modern high- yield agriculture depends upon fertilizers to replace the potassium lost at harvest. Most agricultural fertilizers contain potassium chloride, while potassium sulfate is used for chloride-sensitive crops or crops needing higher sulfur content. The sulfate

4558-588: Is the dynamic viscosity of the fluid, often simply referred to as the viscosity . It is denoted by the Greek letter mu ( μ ). The dynamic viscosity has the dimensions ( m a s s / l e n g t h ) / t i m e {\displaystyle \mathrm {(mass/length)/time} } , therefore resulting in the SI units and the derived units : The aforementioned ratio u / y {\displaystyle u/y}

4664-770: Is the basis of a common method for dating rocks. The conventional K-Ar dating method depends on the assumption that the rocks contained no argon at the time of formation and that all the subsequent radiogenic argon ( Ar ) was quantitatively retained. Minerals are dated by measurement of the concentration of potassium and the amount of radiogenic Ar that has accumulated. The minerals best suited for dating include biotite , muscovite , metamorphic hornblende , and volcanic feldspar ; whole rock samples from volcanic flows and shallow instrusives can also be dated if they are unaltered. Apart from dating, potassium isotopes have been used as tracers in studies of weathering and for nutrient cycling studies because potassium

4770-408: Is the density, J {\displaystyle \mathbf {J} } and q {\displaystyle \mathbf {q} } are the mass and heat fluxes, and D {\displaystyle D} and k t {\displaystyle k_{t}} are the mass diffusivity and thermal conductivity. The fact that mass, momentum, and energy (heat) transport are among

4876-425: Is the local shear velocity. This expression is referred to as Newton's law of viscosity . In shearing flows with planar symmetry, it is what defines μ {\displaystyle \mu } . It is a special case of the general definition of viscosity (see below), which can be expressed in coordinate-free form. Use of the Greek letter mu ( μ {\displaystyle \mu } ) for

4982-611: Is the ratio of extensional viscosity to shear viscosity . For a Newtonian fluid, the Trouton ratio is 3. Shear-thinning liquids are very commonly, but misleadingly, described as thixotropic. Viscosity may also depend on the fluid's physical state (temperature and pressure) and other, external , factors. For gases and other compressible fluids , it depends on temperature and varies very slowly with pressure. The viscosity of some fluids may depend on other factors. A magnetorheological fluid , for example, becomes thicker when subjected to

5088-554: Is the unit tensor. This equation can be thought of as a generalized form of Newton's law of viscosity. The bulk viscosity (also called volume viscosity) expresses a type of internal friction that resists the shearless compression or expansion of a fluid. Knowledge of κ {\displaystyle \kappa } is frequently not necessary in fluid dynamics problems. For example, an incompressible fluid satisfies ∇ ⋅ v = 0 {\displaystyle \nabla \cdot \mathbf {v} =0} and so

5194-477: Is then extracted, usually by cutting, crushing or mashing. The juice is boiled to produce a concentrate and encourage sugar crystallization . The result of this first boiling is called first syrup ('A' Molasses ) and has the highest sugar content. First syrup is usually referred to in the Southern United States as cane syrup rather than molasses. Second molasses ('B' Molasses ) is produced by

5300-490: Is therefore mainly used as an animal feed additive (known as molassed sugar beet feed ) or a fermentation feedstock. Sweet sorghum syrup is colloquially called sorghum molasses in the southern United States . Pomegranate molasses is a traditional ingredient in Middle Eastern cooking. It is made by simmering a mixture of pomegranate juice, sugar and lemon juice and reducing the mixture for about an hour until

5406-410: Is unreactive toward nitrogen and saturated hydrocarbons such as mineral oil or kerosene . It readily dissolves in liquid ammonia , up to 480 g per 1000 g of ammonia at 0   °C. Depending on the concentration, the ammonia solutions are blue to yellow, and their electrical conductivity is similar to that of liquid metals. Potassium slowly reacts with ammonia to form KNH 2 , but this reaction

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5512-415: Is used in several types of magnetometers . Potassium is the eighth or ninth most common element by mass (0.2%) in the human body, so that a 60   kg adult contains a total of about 120   g of potassium. The body has about as much potassium as sulfur and chlorine, and only calcium and phosphorus are more abundant (with the exception of the ubiquitous CHON elements). Potassium ions are present in

5618-410: Is used to treat a kidney stone condition called renal tubular acidosis . Potassium, in the form of potassium chloride is used as a medication to treat and prevent low blood potassium . Low blood potassium may occur due to vomiting , diarrhea , or certain medications. It is given by slow injection into a vein or by mouth. Potassium sodium tartrate ( KNaC 4 H 4 O 6 , Rochelle salt )

5724-460: The Dead Sea is used by Israel and Jordan as a source of potash, while the concentration in normal oceans is too low for commercial production at current prices. Several methods are used to separate potassium salts from sodium and magnesium compounds. The most-used method is fractional precipitation using the solubility differences of the salts. Electrostatic separation of the ground salt mixture

5830-480: The International Union of Pure and Applied Chemistry has designated the official chemical symbol as K . Potassium is the second least dense metal after lithium . It is a soft solid with a low melting point , and can be easily cut with a knife. Potassium is silvery in appearance, but it begins to tarnish toward gray immediately on exposure to air. In a flame test , potassium and its compounds emit

5936-589: The Zahn cup and the Ford viscosity cup —with the usage of each type varying mainly according to the industry. Also used in coatings, a Stormer viscometer employs load-based rotation to determine viscosity. The viscosity is reported in Krebs units (KU), which are unique to Stormer viscometers. Vibrating viscometers can also be used to measure viscosity. Resonant, or vibrational viscometers work by creating shear waves within

6042-411: The chromate ion rather than to that of the potassium ion. There are thousands of uses of various potassium compounds. One example is potassium superoxide , KO 2 , an orange solid that acts as a portable source of oxygen and a carbon dioxide absorber. It is widely used in respiration systems in mines, submarines and spacecraft as it takes less volume than the gaseous oxygen. Another example

6148-425: The density of the fluid ( ρ ). It is usually denoted by the Greek letter nu ( ν ): and has the dimensions ( l e n g t h ) 2 / t i m e {\displaystyle \mathrm {(length)^{2}/time} } , therefore resulting in the SI units and the derived units : In very general terms, the viscous stresses in a fluid are defined as those resulting from

6254-431: The shear viscosity . However, at least one author discourages the use of this terminology, noting that μ {\displaystyle \mu } can appear in non-shearing flows in addition to shearing flows. In fluid dynamics, it is sometimes more appropriate to work in terms of kinematic viscosity (sometimes also called the momentum diffusivity ), defined as the ratio of the dynamic viscosity ( μ ) over

6360-424: The 1960s Canada became the dominant producer. Potassium metal was first isolated in 1807 by Humphry Davy, who derived it by electrolysis of molten caustic potash (KOH) with the newly discovered voltaic pile . Potassium was the first metal that was isolated by electrolysis. Later in the same year, Davy reported extraction of the metal sodium from a mineral derivative ( caustic soda , NaOH, or lye) rather than

6466-491: The BG and EE systems. Nonstandard units include the reyn (lbf·s/in ), a British unit of dynamic viscosity. In the automotive industry the viscosity index is used to describe the change of viscosity with temperature. The reciprocal of viscosity is fluidity , usually symbolized by ϕ = 1 / μ {\displaystyle \phi =1/\mu } or F = 1 / μ {\displaystyle F=1/\mu } , depending on

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6572-468: The Couette flow, a fluid is trapped between two infinitely large plates, one fixed and one in parallel motion at constant speed u {\displaystyle u} (see illustration to the right). If the speed of the top plate is low enough (to avoid turbulence), then in steady state the fluid particles move parallel to it, and their speed varies from 0 {\displaystyle 0} at

6678-434: The alkali in his list of chemical elements in 1789. For a long time the only significant applications for potash were the production of glass, bleach, soap and gunpowder as potassium nitrate. Potassium soaps from animal fats and vegetable oils were especially prized because they tend to be more water-soluble and of softer texture, and are therefore known as soft soaps. The discovery by Justus Liebig in 1840 that potassium

6784-469: The arithmetic and the reference table provided in ASTM D 2161. Potassium Potassium is a chemical element ; it has symbol K (from Neo-Latin kalium ) and atomic number   19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It

6890-425: The bottom to u {\displaystyle u} at the top. Each layer of fluid moves faster than the one just below it, and friction between them gives rise to a force resisting their relative motion. In particular, the fluid applies on the top plate a force in the direction opposite to its motion, and an equal but opposite force on the bottom plate. An external force is therefore required in order to keep

6996-513: The concentration of sodium. Elemental potassium does not occur in nature because of its high reactivity. It reacts violently with water and also reacts with oxygen. Orthoclase (potassium feldspar) is a common rock-forming mineral. Granite for example contains 5% potassium, which is well above the average in the Earth's crust. Sylvite (KCl), carnallite ( KCl·MgCl 2 ·6H 2 O ), kainite ( MgSO 4 ·KCl·3H 2 O ) and langbeinite ( MgSO 4 ·K 2 SO 4 ) are

7102-432: The consistency of syrup is achieved. Many types of molasses on the market are branded unsulfured . In the past, many foods, including molasses, were treated with a sulfur dioxide preservative, helping to kill off moulds and bacteria. Sulfur dioxide is also used as a bleaching agent to help lighten the colour of molasses. Most brands have abandoned the use of sulfur dioxide in molasses because untreated molasses already has

7208-602: The convention used, measured in reciprocal poise (P , or cm · s · g ), sometimes called the rhe . Fluidity is seldom used in engineering practice. At one time the petroleum industry relied on measuring kinematic viscosity by means of the Saybolt viscometer , and expressing kinematic viscosity in units of Saybolt universal seconds (SUS). Other abbreviations such as SSU ( Saybolt seconds universal ) or SUV ( Saybolt universal viscosity ) are sometimes used. Kinematic viscosity in centistokes can be converted from SUS according to

7314-629: The distillation of rum , additive in mortar , and as a soil amendment to promote microbial activity. The unique flavor and nutritional profile of molasses make it a versatile ingredient with both food and non-food applications. The word molasses comes from melaço in Portuguese , a derivative (intensifier) of mel (honey) with Latinate roots. Cognates include Ancient Greek μέλι ( méli ) ( honey ), Latin mel , Spanish melaza (molasses), Romanian miere or melasă , and French mélasse (molasses). Blackstrap

7420-465: The dynamic viscosity (sometimes also called the absolute viscosity ) is common among mechanical and chemical engineers , as well as mathematicians and physicists. However, the Greek letter eta ( η {\displaystyle \eta } ) is also used by chemists, physicists, and the IUPAC . The viscosity μ {\displaystyle \mu } is sometimes also called

7526-435: The element potassium comes from the word potash , which refers to an early method of extracting various potassium salts: placing in a pot the ash of burnt wood or tree leaves, adding water, heating, and evaporating the solution. When Humphry Davy first isolated the pure element using electrolysis in 1807, he named it potassium , which he derived from the word potash . The symbol K stems from kali , itself from

7632-407: The equivalent forms pascal - second (Pa·s), kilogram per meter per second (kg·m ·s ) and poiseuille (Pl). The CGS unit is the poise (P, or g·cm ·s = 0.1 Pa·s), named after Jean Léonard Marie Poiseuille . It is commonly expressed, particularly in ASTM standards, as centipoise (cP). The centipoise is convenient because the viscosity of water at 20 °C is about 1 cP, and one centipoise

7738-409: The fluid do not depend on the distance the fluid has been sheared; rather, they depend on how quickly the shearing occurs. Viscosity is the material property which relates the viscous stresses in a material to the rate of change of a deformation (the strain rate). Although it applies to general flows, it is easy to visualize and define in a simple shearing flow, such as a planar Couette flow . In

7844-459: The fluid is essential to obtain accurate measurements, particularly in materials like lubricants, whose viscosity can double with a change of only 5 °C. A rheometer is used for fluids that cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer. For some fluids, the viscosity is constant over a wide range of shear rates ( Newtonian fluids ). The fluids without

7950-426: The force experienced by a spring is proportional to the distance displaced from equilibrium. Stresses which can be attributed to the deformation of a material from some rest state are called elastic stresses. In other materials, stresses are present which can be attributed to the deformation rate over time . These are called viscous stresses. For instance, in a fluid such as water the stresses which arise from shearing

8056-608: The formation of a surface layer of potassium superoxide , a pressure-sensitive explosive that detonates when scratched. The resulting explosion often starts a fire difficult to extinguish. Potassium is now quantified by ionization techniques, but at one time it was quantitated by gravimetric analysis . Reagents used to precipitate potassium salts include sodium tetraphenylborate , hexachloroplatinic acid , and sodium cobaltinitrite into respectively potassium tetraphenylborate , potassium hexachloroplatinate , and potassium cobaltinitrite . The reaction with sodium cobaltinitrite

8162-405: The friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is negligible in certain cases. For example,

8268-595: The high hydration energy of the K ion, have excellent water solubility. The main species in water solution are the aquo complexes [K(H 2 O) n ] where n = 6 and 7. Potassium heptafluorotantalate ( K 2 [TaF 7 ] ) is an intermediate in the purification of tantalum from the otherwise persistent contaminant of niobium . Organopotassium compounds illustrate nonionic compounds of potassium. They feature highly polar covalent K–C bonds. Examples include benzyl potassium KCH 2 C 6 H 5 . Potassium intercalates into graphite to give

8374-439: The human body. Potassium ions are vital for the functioning of all living cells. The transfer of potassium ions across nerve cell membranes is necessary for normal nerve transmission; potassium deficiency and excess can each result in numerous signs and symptoms, including an abnormal heart rhythm and various electrocardiographic abnormalities. Fresh fruits and vegetables are good dietary sources of potassium. The body responds to

8480-523: The influx of dietary potassium, which raises serum potassium levels, by shifting potassium from outside to inside cells and increasing potassium excretion by the kidneys. Most industrial applications of potassium exploit the high solubility of its compounds in water, such as saltwater soap . Heavy crop production rapidly depletes the soil of potassium, and this can be remedied with agricultural fertilizers containing potassium, accounting for 95% of global potassium chemical production. The English name for

8586-409: The internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's center line than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome

8692-529: The liquid. In this method, the sensor is submerged in the fluid and is made to resonate at a specific frequency. As the surface of the sensor shears through the liquid, energy is lost due to its viscosity. This dissipated energy is then measured and converted into a viscosity reading. A higher viscosity causes a greater loss of energy. Extensional viscosity can be measured with various rheometers that apply extensional stress . Volume viscosity can be measured with an acoustic rheometer . Apparent viscosity

8798-706: The minerals found in large evaporite deposits worldwide. The deposits often show layers starting with the least soluble at the bottom and the most soluble on top. Deposits of niter ( potassium nitrate ) are formed by decomposition of organic material in contact with atmosphere, mostly in caves; because of the good water solubility of niter the formation of larger deposits requires special environmental conditions. Potassium salts such as carnallite , langbeinite , polyhalite , and sylvite form extensive evaporite deposits in ancient lake bottoms and seabeds , making extraction of potassium salts in these environments commercially viable. The principal source of potassium – potash –

8904-435: The most relevant processes in continuum mechanics is not a coincidence: these are among the few physical quantities that are conserved at the microscopic level in interparticle collisions. Thus, rather than being dictated by the fast and complex microscopic interaction timescale, their dynamics occurs on macroscopic timescales, as described by the various equations of transport theory and hydrodynamics. Newton's law of viscosity

9010-490: The name Kalium for Davy's "potassium". In 1814, the Swedish chemist Berzelius advocated the name kalium for potassium, with the chemical symbol K . The English and French-speaking countries adopted the name Potassium , which was favored by Davy and French chemists Joseph Louis Gay-Lussac and Louis Jacques Thénard , whereas the other Germanic countries adopted Gilbert and Klaproth's name Kalium . The "Gold Book" of

9116-418: The reaction of potassium fluoride with calcium carbide was also used to produce potassium. Reagent-grade potassium metal costs about $ 10.00/ pound ($ 22/ kg ) in 2010 when purchased by the tonne . Lower purity metal is considerably cheaper. The market is volatile because long-term storage of the metal is difficult. It must be stored in a dry inert gas atmosphere or anhydrous mineral oil to prevent

9222-468: The reaction, and burning with a lilac - colored flame . It is found dissolved in seawater (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase , a common constituent of granites and other igneous rocks . Potassium is chemically very similar to sodium , the previous element in group 1 of the periodic table. They have a similar first ionization energy , which allows for each atom to give up its sole outer electron. It

9328-564: The recommended daily value of each of those nutrients. Blackstrap is also a good source of potassium . On Madeira Island cane molasses is an important constituent of the traditional cuisine, where it is known as mel-de-cana ( Portuguese for "(sugar)cane's honey"). Its origin in Madeira dates back to the golden age of sugar production in the archipelago. Beet molasses is 50% sugar by dry weight, predominantly sucrose , but contains significant amounts of glucose and fructose . Beet molasses

9434-515: The relative velocity of different fluid particles. As such, the viscous stresses must depend on spatial gradients of the flow velocity. If the velocity gradients are small, then to a first approximation the viscous stresses depend only on the first derivatives of the velocity. (For Newtonian fluids, this is also a linear dependence.) In Cartesian coordinates, the general relationship can then be written as where μ i j k ℓ {\displaystyle \mu _{ijk\ell }}

9540-556: The root word alkali , which in turn comes from Arabic : القَلْيَه al-qalyah 'plant ashes'. In 1797, the German chemist Martin Klaproth discovered "potash" in the minerals leucite and lepidolite , and realized that "potash" was not a product of plant growth but actually contained a new element, which he proposed calling kali . In 1807, Humphry Davy produced the element via electrolysis: in 1809, Ludwig Wilhelm Gilbert proposed

9646-775: The second ionization energy is very high (3052   kJ/mol). Potassium reacts with oxygen, water, and carbon dioxide components in air. With oxygen it forms potassium peroxide . With water potassium forms potassium hydroxide (KOH). The reaction of potassium with water can be violently exothermic , especially since the coproduced hydrogen gas can ignite. Because of this, potassium and the liquid sodium-potassium ( NaK ) alloy are potent desiccants , although they are no longer used as such. Four oxides of potassium are well studied: potassium oxide ( K 2 O ), potassium peroxide ( K 2 O 2 ), potassium superoxide ( KO 2 ) and potassium ozonide ( KO 3 ). The binary potassium-oxygen compounds react with water forming KOH. KOH

9752-828: The surface of the Canadian province of Saskatchewan . The deposits are located in the Elk Point Group produced in the Middle Devonian . Saskatchewan, where several large mines have operated since the 1960s pioneered the technique of freezing of wet sands (the Blairmore formation) to drive mine shafts through them. The main potash mining company in Saskatchewan until its merge was the Potash Corporation of Saskatchewan , now Nutrien . The water of

9858-517: The tanning of leathers . Major potassium chemicals are potassium hydroxide, potassium carbonate, potassium sulfate, and potassium chloride. Megatons of these compounds are produced annually. KOH is a strong base, which is used in industry to neutralize strong and weak acids , to control pH and to manufacture potassium salts . It is also used to saponify fats and oils , in industrial cleaners, and in hydrolysis reactions, for example of esters . Potassium nitrate ( KNO 3 ) or saltpeter

9964-555: The term fugitive elasticity for fluid viscosity. However, many liquids (including water) will briefly react like elastic solids when subjected to sudden stress. Conversely, many "solids" (even granite ) will flow like liquids, albeit very slowly, even under arbitrarily small stress. Such materials are best described as viscoelastic —that is, possessing both elasticity (reaction to deformation) and viscosity (reaction to rate of deformation). Viscoelastic solids may exhibit both shear viscosity and bulk viscosity. The extensional viscosity

10070-715: The term containing κ {\displaystyle \kappa } drops out. Moreover, κ {\displaystyle \kappa } is often assumed to be negligible for gases since it is 0 {\displaystyle 0} in a monatomic ideal gas . One situation in which κ {\displaystyle \kappa } can be important is the calculation of energy loss in sound and shock waves , described by Stokes' law of sound attenuation , since these phenomena involve rapid expansions and compressions. The defining equations for viscosity are not fundamental laws of nature, so their usefulness, as well as methods for measuring or calculating

10176-583: The top plate moving at constant speed. In many fluids, the flow velocity is observed to vary linearly from zero at the bottom to u {\displaystyle u} at the top. Moreover, the magnitude of the force, F {\displaystyle F} , acting on the top plate is found to be proportional to the speed u {\displaystyle u} and the area A {\displaystyle A} of each plate, and inversely proportional to their separation y {\displaystyle y} : The proportionality factor

10282-513: The two systems differ only in how force and mass are defined. In the BG system the pound is a basic unit from which the unit of mass (the slug ) is defined by Newton's Second Law , whereas in the EE system the units of force and mass (the pound-force and pound-mass respectively) are defined independently through the Second Law using the proportionality constant g c . Kinematic viscosity has units of square feet per second (ft /s) in both

10388-403: The viscosity depends only space- and time-dependent macroscopic fields (such as temperature and density) defining local equilibrium. Nevertheless, viscosity may still carry a non-negligible dependence on several system properties, such as temperature, pressure, and the amplitude and frequency of any external forcing. Therefore, precision measurements of viscosity are only defined with respect to

10494-609: The viscosity of a Newtonian fluid does not vary significantly with the rate of deformation. Zero viscosity (no resistance to shear stress ) is observed only at very low temperatures in superfluids ; otherwise, the second law of thermodynamics requires all fluids to have positive viscosity. A fluid that has zero viscosity (non-viscous) is called ideal or inviscid . For non-Newtonian fluid 's viscosity, there are pseudoplastic , plastic , and dilatant flows that are time-independent, and there are thixotropic and rheopectic flows that are time-dependent. The word "viscosity"

10600-571: The viscosity rank-2 tensor is isotropic reduces these 81 coefficients to three independent parameters α {\displaystyle \alpha } , β {\displaystyle \beta } , γ {\displaystyle \gamma } : and furthermore, it is assumed that no viscous forces may arise when the fluid is undergoing simple rigid-body rotation, thus β = γ {\displaystyle \beta =\gamma } , leaving only two independent parameters. The most usual decomposition

10706-500: The viscosity, must be established using separate means. A potential issue is that viscosity depends, in principle, on the full microscopic state of the fluid, which encompasses the positions and momenta of every particle in the system. Such highly detailed information is typically not available in realistic systems. However, under certain conditions most of this information can be shown to be negligible. In particular, for Newtonian fluids near equilibrium and far from boundaries (bulk state),

10812-501: Was first isolated from potash , the ashes of plants, from which its name derives. In the periodic table , potassium is one of the alkali metals , all of which have a single valence electron in the outer electron shell, which is easily removed to create an ion with a positive charge (which combines with anions to form salts ). In nature, potassium occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in

10918-409: Was first suggested in 1702 that they were distinct elements that combine with the same anions to make similar salts, which was demonstrated in 1807 when elemental potassium was first isolated via electrolysis . Naturally occurring potassium is composed of three isotopes , of which K is radioactive . Traces of K are found in all potassium, and it is the most common radioisotope in

11024-443: Was first used by Humphry Davy in 1807. Although the electrolysis process was developed and used in industrial scale in the 1920s, the thermal method by reacting sodium with potassium chloride in a chemical equilibrium reaction became the dominant method in the 1950s. The production of sodium potassium alloys is accomplished by changing the reaction time and the amount of sodium used in the reaction. The Griesheimer process employing

11130-403: Was formerly used as a sedative and in photography. While potassium chromate ( K 2 CrO 4 ) is used in the manufacture of a host of different commercial products such as inks , dyes , wood stains (by reacting with the tannic acid in wood), explosives , fireworks , fly paper , and safety matches , as well as in the tanning of leather, all of these uses are due to the chemistry of

11236-433: Was not understood. Georg Ernst Stahl obtained experimental evidence that led him to suggest the fundamental difference of sodium and potassium salts in 1702, and Henri Louis Duhamel du Monceau was able to prove this difference in 1736. The exact chemical composition of potassium and sodium compounds, and the status as chemical element of potassium and sodium, was not known then, and thus Antoine Lavoisier did not include

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