Chemistry: States and Changes of Matter

Which statement best describes the collisions of gas particles according to the kinetic-molecular theory?

As particles travel in straight lines, their paths sometimes meet, and then they bounce apart with no gain or loss of energy.

Which is a postulate of the kinetic-molecular theory?

Gas particles have a small volume relative to the spaces between them.

A geochemist examines a piece of metal that he found in the soil. He performs tests to identify the metal from its density, electrical conductivity, and melting point. Which statement best describes his investigation?

He is determining physical properties that are sufficient to identify the metal.

Which energy change occurs during boiling?

Heat energy is absorbed by the substance.

Which best describes the energy change that takes place during deposition?

Heat energy is released by the substance.

Why are liquids well suited for hydraulics?

Liquids are incompressible.

How does the motion of particles in the sun's plasma compare to the motion of particles in a solid?

Particles in the plasma move randomly, but particles in a solid vibrate in one place.

Which is an example of the kinetic-molecular theory not holding true for a gas?

The attraction between particles causes a gas to condense at low temperatures.

Which best characterizes a crystal?

a dense substance that is hard and incompressible

Which step will decrease the pressure of a gas inside a closed cubical container?

decreasing the temperature inside the container

Which term best describes liquid behavior under pressure?

incompressible

Which of these is an example of a physical change?

liquid water turning into vapor

Which state of matter is characterized by ionized particles, no definite shape or volume, and good electrical conductivity?

plasma

Which molecules would most likely cause a liquid to have the lowest viscosity?

small, nonpolar molecules

In which phase transition do molecules move directly from a state involving vibration of particles in a fixed position to a state involving random movement of high-speed particles? evaporation

sublimation

The repeating subunits that are responsible for the shape of a crystal are known as

unit cells.

Which description best characterizes the motion of particles in a solid?

vibrating around fixed positions

Which statement best describes the compressibility of a gas?

Increasing the pressure on a gas decreases the volume.

Which statement describes a physical property of copper?

It can be reshaped by a force.

"When nitrogen is liquefied, heat is released." Is this statement true or false?

It is true because heat is released when a gas changes to a liquid.

Which statement describes a chemical property of water?

It reacts with sodium metal.

What happens when the kinetic energy of molecules increases so much that electrons are released by the atoms, creating a swirling gas of positive ions and negative electrons?

Matter changes to a plasma state.

What happens when a solid is dissolved into a liquid?

Solid particles become evenly dispersed among liquid particles.

What happens as a result of the kinetic energy of the particles in a liquid being comparable with the intermolecular attractions between the particles?

The particles move enough that they are not fixed in place, and the liquid can flow.

According to the kinetic-molecular theory, what happens to a liquid when it is transferred from one container to another?

The volume stays the same, but the shape changes to fit the new container.

WRONG: 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

WRONG: ionized plasma.

The particles in water have less mobility than the particles in oxygen. Which statement best explains this observation?

Water particles have strong intermolecular forces.

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?

applying heat to the liquid

Which is an intensive property of a substance?

density

A gaseous substance turns directly into a solid. Which term describes this change?

deposition

Which of these is an example of investigating an intensive property?

determining if a rock is magnetic

Jean has a sample of a liquid. If she changes the liquid's phase by --it, the molecules will spread out, allowing the sample to expand and fill a container of any shape or volume.

evaporating

Which sequence represents the relationship between pressure and volume of an ideal gas as explained by the kinetic-molecular theory?

smaller volume ----> crowded particles ------> more collisions ----> higher pressure

A solid substance turns directly into a gas. Which term describes this change?

sublimation

Which is an aspect of the kinetic-molecular theory and can be used to explain the compressibility of plasmas?

Particles move independently of one another and are widely spaced.

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?

Substance X is a solid, and substance Y is a plasma.

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?

The scientist is observing an intensive property of a superconductor.

Which statement describes a limitation of the kinetic-molecular theory for a gas?

The theory assumes that particles do not experience intermolecular forces.

Why do amorphous solids not have a long-range order in the arrangement of their particles?

Their formation involves very rapid cooling.

Which best explains why a crystal is incompressible?

There is little, if any, space left between its adjacent molecules.

Which statement about gases is true?

They are made up of hard spheres that are in random motion.

Glycerol boils at a higher temperature than water. What does this indicate about the attractive forces of glycerol?

They are stronger than those in water.

Which postulate of the kinetic-molecular theory applies to the particles of a liquid?

They have enough kinetic energy to easily slide by each other.

WRONG: Which observation indicates that the kinetic-molecular theory has limited use for describing a certain gas?

WRONG: Increasing pressure is reducing the volume of the gas.

WRONG: Which reason best explains why plasmas are good conductors of electricity?

WRONG: They are at extremely high temperatures.

WRONG: The closeness of particles of gas and their low speeds allow intermolecular forces to become important at certain pressures and temperatures. Which best describes this statement?

WRONG: This describes ideal gas behavior using the kinetic-molecular theory.

WRONG: Which two conditions can limit the usefulness of the kinetic-molecular theory in describing gas behavior?

WRONG: low pressure and medium temperatures

Water can dissolve other substances. Which factor best contributes to this property of water?

Water particles are not fixed in place.

Step 1: She pours a colorless solution into a beaker that contains another colorless liquid. Yellow particles appear in the liquid. Step 2: She lets the yellow particles settle in the beaker and then separates the colorless liquid by decantation. What has most likely occurred in the beaker?

a chemical change in step 1 and a physical change in step 2

In the diagram below, particles of the substance are moving from the liquid phase to the gas phase at the same rate as they move from the gas phase to the liquid phase.

equilibrium.

Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular theory?

higher temperature more kinetic energy more space between particles higher volume

Which of these is an extensive property of a substance?

volume

A graph of gas pressure versus the number of particles in a container is a straight line. Which other relationship will have a similar graph?

volume versus temperature, because they are also directly proportional