If water is added it is miscible with the emulsion.Oil is the dispersed phase and water is a dispersion medium.Characteristics of Oil in Water Emulsions: The emulsifier is dissolved in water and oil is added to it drop by drop with continuous agitation. Milk is (fats) oil in water type of emulsion, vanishing creams.
In this type of emulsion, oil is the dispersed phase and water is the dispersion medium. Types of Emulsions and Their Preparation: Soaps, Detergents, Lyophilic substances like gelatin, gum etc. Emulsifier forms a protective layer around disperse phase droplets and prevent coagulation. This third substance is called Emulsifying agent or Emulsifier. To obtain a stable emulsion a small quantity of third substance is added along with two immiscible liquids. The liquid in excess is the dispersion medium and the liquid which forms droplets or globules is the dispersed phase.Įmulsions of oil and water are unstable and sometimes they separate into two layers on standing. Generally, one of the two liquids is water and the other which is immiscible with water is designated as oil. Milk, cod liver oil, oil paints, vanishing cream, cold creams, etc. More about the Cobalt Chloride in Wikipedia.Science > Chemistry > Colloids > EmulsionsĪ colloidal system in which both the dispersed phase as well as dispersion medium are immiscible or partially miscible liquids is called an emulsion. Cobalt chloride is one method used to induce pulmonary arterial hypertension in animals for research and evaluation of treatment efficacy. Cobalt chloride is a banned substance under the Australian Thoroughbred Racing Board. Cobalt supplementation is not banned and therefore would not be detected by current anti-doping testing. Cobalt chloride is an established chemical inducer of hypoxia-like responses such as erythropoiesis. Invisible ink: when suspended in solution, cobalt(II) chloride can be made to appear invisible on a surface when that same surface is subsequently exposed to significant heat (such as from a handheld heat gun or lighter) the ink permanently/ irreversibly changes to blue. Cobalt(II) chloride catalyzes cross-coupling of aryl halides or vinyl halides with aryl Grignard reagents in excellent yields. Cobalt chloride is useful for producing invisible ink as it turns blue when heated and becomes invisible once it gets cooled. Cobalt chloride is an indicator for water in desiccants, owing to the reversible hydration/dehydration coupled with distinct color change. In the anhydrous form, it finds use in electroplating of cobalt, in organic chemistry and is a precursor to cobaltocene, (bis(cyclopentadienyl)cobalt(II), which is a good reducing agent.
hydrated) ApplicationsĬobalt(II) chloride is used in humidity indicator in weather instruments. Desiccants such as silica gel can incorporate cobalt chloride to indicate when it is "spent" (i.e. It is impregnated into a paper to make test strips for detecting moisture in solutions, or more slowly, in air/gas. The colour change is from a shade of blue when dry, to a pink when hydrated, although the shade of colour depends on the substrate and concentration. Arte Fo supplies cobalt (II) chloride anhydrous with 99,8% purity (metals basis) in several amounts.Ĭobalt chloride is a common visual moisture indicator due to its distinct colour change when hydrated. It is generally supplied in bead form and should be handled carefully as it is a suspected carcinogen. Analytical research gradeĬobalt (II) chloride anhydrous, also known as Cobaltous Chloride, is a beautiful sky blue color.
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