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Be sure that math assignments completed by our experts will be error-free and done according to your instructions specified in the submitted order form. Our experts will gladly share their knowledge and help you with programming projects. General Chemistry. The viscosity of a liquid always decreases as temperature increases. As the molecules acquire more energy, they can escape from their mutual traction more readily. Long-chain molecules can also wriggle around more freely at a higher temperature and hence disentangle more quickly.
Below is a video that demonstrates this effect with a household liquid: honey. Egas , Isabel M. Fonseca , Ana C. Costa , Danielly C. The viscosity of glycerol. Ngai , Fabio Sterpone , Alessandro Paciaroni. Critical structural fluctuations of proteins upon thermal unfolding challenge the Lindemann criterion. Proceedings of the National Academy of Sciences , 35 , Physical Chemistry Chemical Physics , 19 7 , Aggregation-induced emission properties of hydrothermally synthesized Cu—In—S quantum dots.
Chemical Communications , 53 23 , Study of binary system glycerine—water and its colloidal samples of silver nanoparticles. Eugene Stanley. MRS Advances , 1 26 , Influence of temperature and concentration on tribological properties of silicon nitride in glycerol aqueous solution.
Ceramics International , 42 3 , Chemistry - A European Journal , 21 30 , Rhamnolipid based glycerol-in-diesel microemulsion fuel: Formation and characterization. Fuel , , Concentration and temperature dependence of the viscosity of polyol aqueous solutions. Cryobiology , 69 1 , Lerch , Zhongyu Yang , Evan K.
Brooks , Wayne L. Mapping protein conformational heterogeneity under pressure with site-directed spin labeling and double electron—electron resonance. Boundary and elastohydrodynamic lubrication studies of glycerol aqueous solutions as green lubricants. Tribology International , 69 , The Journal of Physical Chemistry C , 47 , Computational fluid dynamics modelling of perfusion measurements in dynamic contrast-enhanced computed tomography: development, validation and clinical applications.
Physics in Medicine and Biology , 58 17 , Eloi , M. First you crush some crystals of potassium permanganate to a fine powder, then you make it into a volcano-cone shaped heap, on a heat-proof mat.
Just make a small dent in the top of the cone, then get a dropping pipette and slowly drip the glycerol onto it. After a few seconds, the mixture starts smoking and then it bursts into flames at the top. Glycerol is not a hydrocarbon, of course, as it has oxygen in it, but you can explain that the carbon it contains is oxidised to carbon dioxide and the hydrogen is oxidised to water , in an exothermic reaction that is like a fuel being burned. We normally meet glycerol as a rather syrupy colourless liquid, much more viscous than water or alcohol.
The reason for this is that each of the three carbon atoms in the glycerol molecule has an OH or hydroxyl group attached. These three OH groups can bind to other hydroxyl groups, either in water molecules — which makes glycerol very soluble in water — or by hydrogen-bonding with other glycerol molecules.
Hydrogen-bonding creates an aggregation that means that glycerol does not flow as well as water, so neat glycerol is rather viscous. The ability of glycerol to hydrogen-bond with water means that when a glycerol-water mixture is cooled, it has to reach quite a low temperature before ice crystals start to form, and this is the basis of using glycerol in antifreeze for cars.
Other polyols like ethane-1,2-diol ethylene glycol also do this — ethylene glycol is cheaper than glycerol, so that is the molecule usually used in antifreeze. Unfortunately, unlike glycerol, ethylene glycol is very toxic and regularly causes fatalities when children or pets drink antifreeze.
Glycerol is very safe, and possibly the most risky thing associated with glycerol is its use in laxatives. Glycerol is also an important chemical used to make various other chemicals, the best known being the explosive materials nitroglycerine and dynamite.
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