A mixture of biodiesel and gasoline could be distinguished from one another, but

Question

A mixture of biodiesel and gasoline could be distinguished from one another, but a solution of petroleum diesel and biodiesel could not. What value from the table above shows this trend? A solution of pure biodiesel could be distinguished from a solution of pure petroleum diesel by their different viscosity. In your own words, what is viscosity? Name two substances that are viscous. How would you expect the viscosity of fuel to affect its performance on a cold day (think about a cold day in the winter)? Which of the fuels listed

Explanation / Answer

1. The table is not properly shown.

2. Petroleum Diesel

Generally, diesel fuel is liquid fuel to power diesel engines used mainly in road vehicles, water crafts, rail vehicles and stationary engines. It is a hydrocarbon mixture with approx. 8 to 21 carbon atoms per molecule obtained by crude oil distillation. Additionally, it contains additives. The most common grade is diesel fuel No. 2. An important parameter for the quality of a diesel fuel is the cetane number. The minimum cetane number is 51 according to EN 590. Higher cetane numbers are an indicator of better ignitability of the fuel when injected into the cylinder filled with hot compressed air. Viscosity is generally an important parameter for diesel fuel. Fuel which is too highly viscous can cause damage in the fuel pump (e.g. cam and follower wear) due to higher pressure. Too low viscosity may lead to a lack of lubrication. Viscosity also influences the fuel delivery rate and the atomization of the fuel during injection.

Biodiesel

Biodiesel or FAME (fatty acid methyl ester) is an alternative diesel fuel derived from renewable feedstocks such as used cooking oils, rapeseed oil, animal fat or soybean oil. It is obtained by transesterification. Pure biodiesel is known as B100. Mixtures of biodiesel with petroleum diesel are named as BXX, where XX is the percentage of biodiesel in the blend.
By the way - petroleum diesel also contains up to 7 % biodiesel according to country-specific laws.

The sizes of the molecules in biodiesel and petroleum diesel are about the same, but they differ in chemical structure. Biodiesel molecules consist almost entirely of chemicals called fatty acid methyl esters (FAME), which contain unsaturated “olefin” components. Low-sulfur petroleum diesel, on the other hand, consists of about 95 percent saturated hydrocarbons and 5 percent aromatic compounds.Biodiesel has higher lubricity (it is more “slippery”) than petroleum diesel. This is a good thing, as it can be expected to reduce engine wear.
Biodiesel contains practically no sulfur. This is also a good thing, as it can be expected to result in reduced pollution from engines using biodiesel.
Biodiesel has a higher oxygen content (usually 10 to 12 percent) than petroleum diesel. This should result in lower pollution emissions. But, relative to petroleum diesel, it causes slightly reduced peak engine power (~4 percent).With Length of molecule increases the cetane number, heat of combustion; decreases NOx emissions and Increases viscosity. With Saturation Decreases NOx emissions, improves oxidative stability, reduces deposition and Increases melting point and viscosity; reduces lubricity.

Viscosity is physical property of a material which a fluid resists a tendency to flow. The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress.Viscosity is the ability of substances, especially fluids, to resist flow. For liquids, it corresponds to the informal concept of "thickness"; for example, honey has a much higher viscosity than water.

Examples oils, honey, glycerin, tar and sulfuric acid.

3. The temperature dependence of liquid viscosity is the phenomenon by which liquid viscosity tends to decrease (or, alternatively, its fluidity tends to increase) as its temperature increases. This can be observed, for example, by watching how cooking oil appears to move more fluidly upon a frying pan after being heated by a stove. Kinematic viscosity can be estimated as a typical (thermal) velocity times the mean free path. A molecular view of liquids can be used for a qualitative picture of decrease in the shear (or bulk) viscosity of a simple fluid with temperature. As the temperature increases, the thermal velocity increases. However, much more important is the rapid decrease of the mean free path with temperature. The reason for this is that temperature increase releases more and more molecules to move around and interact with any given molecule. The actual process can be quite complex and is typically represented by simplified mathematical or empirical models, some of which are discussed below. The models are valid over limited temperature ranges and for selected materials.The former effect causes a decrease in the shear stress while the latter causes it to increase. The result is that liquids show a reduction in viscosity with increasing temperature. With high temperatures, viscosity increases in gases and decreases in liquids, the drag force will do the same.

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