A substance is tested in a lab. It is found to maintain a unique shape and is a good conductor of electricity. If it is made up of electrons, protons, and neutrons, what state of matter is this substance most likely to be?

• gas

• liquid

• plasma

• solid

Answer explanation

A solid has a definite shape and conducts electricity when its particles are arranged in a rigid structure that allows electron flow.

Tags

NGSS.HS-PS1-3

A substance is examined under the kinetic-molecular theory. It is observed to explain the behavior of plasmas. What is an aspect of this theory related to the examined substance?

•  Particle spacing can allow a very high density.

• Particle kinetic energy is independent of temperature.

• Particles vibrate quickly in stationary positions.

• Particles exchange energy through elastic collisions.

Answer explanation

The kinetic-molecular theory explains plasmas by noting that particles exchange energy through elastic collisions, conserving total energy.

Tags

NGSS.HS-PS3-2

A technology involves the use of a specific state of matter. It is implemented in certain devices. Which device is most likely to utilize this state?

• arc welder

• diesel engine

• car radio

• battery-operated flashlight

Answer explanation

Arc welders use plasma arcs, where ionized gases conduct electricity and generate the heat needed for welding.

Tags

NGSS.HS-PS2-5

 A characteristic of materials is their structure. It is related to the order within the material. Which of the following materials is best identified by having a long-range order?

• in amorphous solids

• in crystalline solids

•  in thermal plasmas

• in nonthermal plasmas

Answer explanation

Crystalline solids have particles arranged in a repeating, long-range order, unlike amorphous solids.

A table compares solids and plasmas. It describes various characteristics. What statement accurately completes the comparison? Solids: are made of neutral particles or cation-anion pairs, are the lowest-energy form of matter, resist changes in shape or volume Plasmas: ?, are the highest-energy form of matter, are highly compressible

• can be crystalline

• can be amorphous

• are made of charged particles

• are made of neutral particles

Answer explanation

Plasmas are made of charged particles (ions and electrons), which differentiates them from neutral solids.

A use of a certain state of matter in technology is categorized. It involves different applications. Which application uses this state most likely?

• taking pictures of solar flares

• observing the aurora borealis

• making fluorescent lights for houses

• making telescopes to observe distant stars

Answer explanation

Fluorescent lights work by exciting gases into the plasma state, which then emit visible light.

Tags

NGSS.HS-PS4-5

A low-energy state of condensed matter is characterized. It involves structural rigidity and resistance to changes. What state is described?

• gas

• liquid

• plasma

• solid

Answer explanation

Solids are the low-energy, rigid state of matter that resist changes in shape or volume.

The motion of particles in two different states of matter is compared. One is found in the sun, the other in a more stable form. How does their motion differ?

• Particles in both the plasma and a solid move around to fill available space.

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

• Particles in the plasma have low kinetic energy, but particles in a solid have high kinetic energy.

• Particles in both the plasma and a solid are made up of fast-moving electrons and cations.

Answer explanation

Plasma particles move freely and randomly, while solid particles only vibrate around fixed positions.

Tags

NGSS.MS-PS1-4

A state of matter is characterized by specific properties. It includes ionized particles and electrical conductivity. Which state is described?

• gas

• liquid

• plasma

• solid

Answer explanation

Plasmas are ionized, conductive, and lack a fixed shape or volume, unlike gases or solids.

Two substances, X and Y, are compared based on volume and particle attraction. One has a fixed volume; the other is compressible. What conclusion is most likely?

• Substance X is a crystal, and substance Y is a liquid.

• Substance X is a gas, and substance Y is a plasma.

• Substance X is a plasma, and substance Y is a crystal.

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

Answer explanation

A solid has fixed volume and strong particle attraction, while plasma has spread-out, compressible charged particles.