Heat and Matter

Which of the following changes made to a sample of liquid would result in an increase in the distance between the individual molecules of the substance?

• Transferring the substance to a smaller container

• Adding heat energy to the substance

• Changing the phase of matter from liquid to solid

• Decreasing the overall kinetic energy of the liquid

A student drew a representation of the atoms of a solid. The drawing shows closely packed atoms vibrating, but remaining in the same relative positions.

Which of the following must the student change to make the illustration accurately represent the same substance in the liquid phase?

• The drawing should show increased movement of the atoms

• Each individual atom should be much larger

• There should be very wide spaces between the atoms

• The shape of each atom must reflect the shape of the container

Tags

NGSS.MS-PS1-4

As thermal energy is added to a substance, which of the following changes can be predicted?

• Spacing between particles will decrease

• Vibration of individual particles will increase

• Temperature of the substance will decrease

• The pressure of the air around the substance will increase

Which of the following statements best describes the relationship between temperature and kinetic energy of particles in a substance?

• As kinetic energy decreases, temperature is not affected

• As kinetic energy increases, temperature decreases

• As kinetic energy decreases, temperature increases

• As kinetic energy increases, temperature increases

Temperature is not a direct measure of the thermal energy of a system. The total thermal energy of a system depends on its temperature and what other factors? Choose all that apply.

• The temperature of the system’s environment and its location in that environment

• The number of atoms in the system and their molecular weights

• The boiling points & freezing points of the elements that make up the substances in the system

• The number of atoms in the system and conductivity of the material

Students were asked to draw a concept map of changes in matter at the molecular level. An incomplete sample is provided here. Which of the following labels would be most appropriate for completing the diagram?

• Arrow A = particles become more tightly packed

• Arrow B = the pressure of the substance increases

• Arrow C = kinetic energy of particles increases

• Arrow D = particles move at a quicker pace

What happens to water molecules when a large quantity of thermal energy is added to water in the liquid state?

• The more thermal energy added, the greater the attraction between molecules.

• The molecules gain kinetic energy, move farther apart, and become a gas.

• The water molecules become packed closer together, and their temperature increases.

• Each water molecule gives up kinetic energy and eventually stops moving.

In science, the term “heat” is used to describe which of the following?

• The motion of atoms or molecules within a substance

• The transfer of thermal energy from one object to another

• The average temperature of a system over time

• The average kinetic energy of the system as a whole

Thermal energy is removed from a sample of helium. All of the following changes will result from this EXCEPT–

• the molecules will become more packed.

• the temperature of the system will decrease.

• total energy in the system increases.

• the molecules of the system will lose kinetic energy.

When thermal energy is removed from a system, what happens to the temperature and the average kinetic energy of the system?

• Temperature decreases, average kinetic energy increases

• Temperature decreases, average kinetic energy decreases

• Temperature increases, average kinetic energy increases

• Temperature increases, average kinetic energy decreases