A
The property that describes a liquid’s thickness or thinness is called ________
viscosity.
Materials with low viscosity ___________
flow easily,
______ is one of the strangest substances in the universe. Although it is commonly used in its gaseous state, it has unusual properties as a liquid.
Helium
__________ are so far apart, and the attractive forces are so low, that the type of gas particle is less important than in a liquid.
Gas particles
If the candy were to stay too hot for too long, it might become ___________
too hard to bite.
A thicker liquid is more ______ and has a higher viscosity.
viscous
Materials with high viscosity ___________
move more slowly.
At a few degrees above absolute zero (about –270°C), helium changes from a “normal” fluid to a ________,
superfluid
Resistance to flow creates _________.
internal friction
Nail polish is applied as a slick fluid, but dries into a solid finish. Mascara is a very thick fluid, which dries extremely quickly after it is applied. How is the viscosity of these products controlled?
The viscosity of both of these products is controlled by the amount of solvent that is added.
Viscosity in ______ increases and decreases in a different way than it does for liquids.
gases
Does water have low or high Viscosity?
Low Viscosity:
A substance that can flow without friction is known as a _________
superfluid,
What causes friction?
Friction is caused when two surfaces are rubbed together.
Why does a chef need to know how to adjust the viscosity of a substance to suit specific applications?
Chefs need to know how to make gravies thinner than sauces and frostings thicker than icings.
You could measure the time it takes for the fluid to flow from one point to another point. This measurement is called _________
the fluid’s flow rate.
Does honey have low or high Viscosity?
High Viscosity
Superfluids have zero ______ and no internal resistance to flow.
viscosity
According to the particle model, as the temperature of a material increases, the attractive forces between the particles of the material _________
decrease.
Why does a mechanic need to know how to adjust the viscosity of a substance to suit specific applications?
Mechanics must choose an engine oil that is the right viscosity for the season.
Why are lubricants used in machines ?
Lubricants are used in machines to reduce the friction between moving parts.
What is the effect of temperature on the flow rate — and thus the viscosity — of a liquid?
Temperature has a significant effect on the flow rate and viscosity of a liquid. As temperature increases, the viscosity decreases. When temperature decreases, viscosity increases, and the liquid becomes thicker and flows more slowly.
Heated gases flow less quickly and smoothly because of an increased number of collisions among particles at ______________
higher temperatures.
_________for candy bars must be at precisely the right consistency and temperature in order to cover the bar completely with the same amount of chocolate each time.
chocolate coating
Why does an artist need to know how to adjust the viscosity of a substance to suit specific applications?
Artists need to know how to thin or thicken oil paints or acrylics.