Unit 4 Test
nonthermal plasma.
A plasma that has particles that never collide frequently enough to exchange kinetic energy and never reach a temperature equal to the surroundings is categorized as a
The scientist is observing an intensive property of a superconductor.
A scientist observes that the electrical resistance of a superconducting material drops to zero when the material is cooled to very low temperatures. Which of the following statements best describes what the scientist is observing?
It is not a gas because its particles do not have large spaces between them.
A substance is made up of slow-moving particles that have very little space between them. Based on this information, what can most likely be concluded about this substance?
neither attraction nor repulsion.
According to the kinetic-molecular theory, the collision between two ideal gas particles is a result of
The soap reduced the surface tension behind the boat, causing both water molecules and the boat to be pulled forward.
Carla makes a small cardboard boat and floats it in a tub of water. When she adds a drop of dish soap behind the boat, the boat moves forward. Which statement best explains what happened?
They are stronger than those in water.
Glycerol boils at a higher temperature than water. What does this indicate about the attractive forces of glycerol?
higher gas pressure
If gas particles start colliding with the walls of their metallic container with increased force, what is their direct effect?
leave little space between the molecules.
Liquids and solids are referred to as "condensed phases" because the attractive forces
gain enough kinetic energy to get past each other.
Melting can be best described as a process in which molecules
Substance X is a solid, and substance Y is a plasma.
Substance X has a fixed volume, and the attraction between its particles is strong. Substance Y has widely spread out particles and can be compressed. What can most likely be concluded about these substances?
applying heat to the liquid
Valerie wants to examine the properties of a thick liquid but is finding it difficult to pour the liquid into a beaker. She needs to finish her investigation before the end of class. Which method will allow her to pour the liquid easily?
plasmas that reach a temperature equal to their surroundings
What are thermal plasmas?
Solid particles become evenly dispersed among liquid particles.
What happens when a solid is dissolved into a liquid?
surface tension
What is produced on the top of a pool of water by the mutual attraction between water molecules?
Heat energy is released by the substance.
Which best describes the energy change that takes place during deposition?
A liquid evaporates faster at higher temperatures because more particles have a higher speed and can overcome attractions in the liquid.
Which best explains the relationship between evaporation and temperature?
There is little, if any, space left between its adjacent molecules.
Which best explains why a crystal is incompressible?
vibrating around fixed positions
Which description best characterizes the motion of particles in a solid?
freezing ice cream
Which example involves a phase change in which heat energy is released by the substance?
auroras
Which is an example of plasmas in nature?
The attraction between particles causes a gas to condense at low temperatures.
Which is an example of the kinetic-molecular theory not holding true for a gas?
density
Which is an intensive property of a substance?
boiling point, conductivity, and color
Which list includes only physical properties?
small, nonpolar molecules
Which molecules would most likely cause a liquid to have the lowest viscosity?
determining if a rock is magnetic
Which of these is an example of investigating an intensive property?
volume
Which of these is an extensive property of a substance?
determine the density
Which procedure could a student use to examine an intensive property of a rectangular block of wood?
boiling
Which process most likely takes place when the kinetic energy of molecules overcomes the intermolecular forces?
Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular theory?
Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular theory?
plasma
Which state of matter is characterized by ionized particles, no definite shape or volume, and good electrical conductivity?
They are made up of hard spheres that are in random motion.
Which statement about gases is true?
As particles travel in straight lines, their paths sometimes meet, and then they bounce apart with no gain or loss of energy.
Which statement best describes the collisions of gas particles according to the kinetic-molecular theory?
it can be reshaped by a force
Which statement describes a physical property of copper?
high pressure and low temperatures
Which two conditions can limit the usefulness of the kinetic-molecular theory in describing gas behavior?
Liquids are incompressible.
Why are liquids well suited for hydraulics?
an amorphous solid because the particles do not have a regular structure
group of students are wandering around a room. When their teacher claps, the students sit down wherever they are. This situation best models the formation of which type of solid?
