Viscosity is a measure of a fluid’s resistance to flow. A fluidwith large viscosity resists motion because its molecular makeup gives it a lot of internal friction. A fluid with low viscosity flows easily because its molecular makeup results in very little friction when it is in motion.

The viscosity of a liquid usually depends on its temperature. Viscosity generally decreases as the temperature increases. Viscosity generally increases as the temperature decreases. The viscosity of a liquid is related to the ease with which the molecules can move with respect to one another.

In the SI unit, the value of viscosity is 8.90 × 10 ^ – 4 Pa·s. In CGS unit, the value of viscosity is 8.90 × 10 ^ – 3 dyn·s/cm ^ 2 or 0.890 cP.

Viscosity is caused by friction within a fluid. It is the result of intermolecular forces between particles within a fluid.

The viscosity of liquids decreases rapidly with an increase in temperature, and the viscosity of gases increases with an increase in temperature. Thus, upon heating, liquids flow more easily, whereas gases flow more sluggishly.

Viscosity is governed by the strength of intermolecular forces and especially by the shapes of the molecules of a liquid. Liquids whose molecules are polar or can form hydrogen bonds are usually more viscous than similar nonpolar substances.

A petroleum refinery process used to lower or break the viscosity of high-viscosity residuum by thermal cracking of molecules at relatively low temperatures. Also known as visbreaking.

Glycol has maximum viscosity because it has two −OH groups and there is greater intermolecular H−bonding in comparison to water and methanol. Kerosene is a mixture of hydrocarbons.

Ethyl alcohol is the least viscous fluid that you could (A) acquire a large enough quantity to swim in, and (B) not die from dipping your body into it.

Water, gasoline, and other liquids that flow freely have a low viscosity. Honey, syrup, motor oil, and other liquids that do not flow freely, like those shown in Figure 1, have higher viscosities.

Fluids with low viscosity have a low resistance and shear easily and the molecules flow quickly; high viscosity fluids move sluggishly and resist deformation. Some liquids, like pitch, glass and peanut butter, have such high viscosity they behave like solids. For example, water at 20°C has a viscosity of 1.002 cPs.

Common Units

The fluid found inside the hollow coconut chamber, the coconut water, is a surprisingly good substitute, as it’s nearly identical to human blood plasma: it’s nutritive, sterile, and contains various minerals and amino acids.

between 3.5 and 5.5 cP

Preparation

1. Prepare the fake blood.
2. Thoroughly mix two tbsp.
3. Add four tbsp.
4. Mix in one teaspoon of red (or other color) food coloring.
5. You should now have a small bowl of fake blood (or other liquid, if you prefer less gore!).
6. Be careful not to spill the fake blood on furniture or carpeting—it can stain!

You can make a simple, highly effective fake blood that’s water-soluble and nonstaining with just three ingredients: clear corn syrup, washable red poster paint and cocoa powder.