Particle Motion & States of Matter
In this state of matter, particles are packed tightly together and vibrate in place.
What do we call the phase change when a liquid turns into a gas?
Evaporation
What is the name of the heat transfer method that requires direct contact between objects?
Conduction
You burn your hand by touching a hot stove burner.
Conduction
What do we call the total kinetic energy of all the particles in an object?
Thermal Energy
In this state of matter, particles move freely and spread out to fill any container.
Gas
What happens to the particles of ice when it melts into water?
Move faster / Spread apart
Heat transfer through electromagnetic waves that can travel through empty space is called ___________.
Radiation
The sun warms your face on a cold day.
Radiation
A material that does NOT transfer heat easily is called a(n) ___________.
Insulator
When you add thermal energy to particles, they move ___________.
Faster
When water vapor touches a cold glass and turns back into liquid, what phase change is happening?
Condensation
When hot air rises and cool air sinks, creating a circular movement, this is an example of ___________.
Convection
A heater on the floor warms a whole room as hot air rises and spreads.
Convection
A material that easily allows heat to transfer through it is called a(n) ___________.
Conductor
Which state of matter has particles that are close together but can still flow past each other?
Liquid
Does freezing lose or gain thermal energy?
lose — it gives off energy to the surroundings
A wooden spoon and a metal spoon are both left in a pot of boiling soup. Which one would you rather grab, and what does that tell you about the two materials?
A: The wooden spoon — wood is an insulator and conducts heat slowly; metal is a conductor and transfers heat quickly to your hand
A metal spoon sits in a hot bowl of soup. Name the heat transfer method AND explain why the handle gets warm even though only the tip is touching the soup.
A: Conduction — thermal energy transfers from particle to particle through the metal up to the handle
What is the difference between heat and temperature?
A: Temperature measures the average kinetic energy of particles; heat is the transfer of thermal energy between objects
An ice cube is placed in a warm hand and begins to melt. What is happening to the particles in the ice, and which direction is thermal energy flowing? A: Particles gain energy and move faster; thermal energy flows from the warm hand into the cooler ice
Gain energy/ Move faster. Energy flows from hand to ice
A puddle disappears on a warm day even though it never boiled. What phase change explains this, and where did the energy come from?
Evaporation — the water absorbed thermal energy from the sun, air, or ground
Explain why convection cannot happen in a solid.
A: Convection requires particles to flow and circulate —such as in a liquid or gas.
You're at a bonfire with friends. Name three heat transfer methods and give one example of each that could happen at the bonfire.
Conduction- touching fire
Convection - smoke from fire
Radiation - feeling its heat
A metal chair left outside feels colder than a wooden chair on the same cold morning. They are the same temperature. Using the words conductor and insulator, explain why the metal feels colder.
Metal is a conductor — it transfers thermal energy away from your body quickly, making it feel cold.
Wood is an insulator — it transfers heat slowly, so it feels warmer even at the same temperature.