Seperation Methods
What method uses a filter to remove undissolved solids from a liquid?
Filtration.
What is a mixture that looks the same throughout called?
Homogeneous mixture.
What is a fluid's resistance to flowing called?
Viscosity.
What device controls fluid flow through a pipe?
A valve.
What are the tanks used to control a submarine's buoyancy called?
Ballast tanks.
What is the process of removing salt from seawater called?
Desalination.
What is a mixture that is not uniform throughout called?
Heterogeneous mixture.
Which usually flows more slowly: honey or water?
Honey.
What fluid does a hydraulic system use to transmit force?
A liquid.
What happens when seawater fills a submarine's ballast tanks?
Its average density increases, allowing it to sink.
What method removes water from food to help preserve it?
Dehydration.
What cleaning agent in detergents helps remove grease?
Surfactant.
What generally happens to a liquid's viscosity when it is heated?
It decreases.
What happens when the diaphragm in a pump moves upward?
Pressure decreases, allowing fluid to enter.
What device is pushed through natural gas pipelines to clean or inspect them?
Pipeline pig.
What two changes of state are used to collect a liquid during distillation?
Evaporation (or boiling) and condensation.
Why does dissolved salt pass through an ordinary coffee filter?
Dissolved salt is not trapped by the filter; it passes through with the water.
What happens to air pressure when air is compressed?
It increases.
How does an Archimedes' screw move water uphill?
A rotating spiral carries pockets of water upward.
Why would scientists use ROPOS instead of sending people into the deep ocean?
ROPOS is remotely operated, allowing scientists to explore underwater environments and collect information without putting people at risk.
Why is fractional distillation useful for separating petroleum?
Its components have different boiling ranges, so they can be separated into fractions.
In gold extraction, what passes through the filter after chemicals dissolve the gold?
The solution containing dissolved gold; undissolved waste is trapped.
Why can rising too quickly from a deep dive cause the bends?
Dissolved nitrogen can form bubbles in the body as pressure decreases.
Why does pushing down a bicycle pump piston force air into the tire?
The air is compressed, increasing its pressure above the pressure inside the tire.
How does a submarine rise to the surface using its ballast tanks?
Compressed air pushes water out of the tanks, decreasing the submarine's average density and allowing it to rise.