thermal energy
What is the total energy of all particles in a substance called?
Thermal energy.
What type of energy is associated with motion?
Kinetic energy.
What measures the average kinetic energy of particles in a substance?
Temperature.
You touch a metal chair and it feels cold. What does this tell you about the temperature of the metal compared to your hand?
The metal is at a lower temperature, so heat flows from your hand to the metal.
When you heat a cup of cocoa, what type of energy is being transferred from the stove to the drink?
Thermal energy.
What happens to the kinetic energy of particles when temperature increases?
kinetic energy increases.
When particles slow down, what happens to the temperature?
When particles slow down, what happens to the temperature?
A cup of hot chocolate cools down after sitting on the table for 15 minutes. Why does this happen?
Heat transfers from the hot chocolate to the cooler air until they reach the same temperature.
Thermal energy depends on both the temperature and what other factor?
The number of particles or the mass of the substance.
If particles in one substance move faster than in another, which substance has more kinetic energy?
The one with faster-moving particles.
Why does temperature not depend on the amount of substance?
Because temperature is the average energy, not the total.
Two beakers of water are both 60°C. Beaker A has 100 mL of water and Beaker B has 300 mL. Which one has a higher temperature?
Neither—they have the same temperature.
Two objects are the same temperature, but one is larger. Which has more thermal energy and why?
The larger object, because it has more particles.
Why does a solid have less kinetic energy than a liquid or gas?
Because its particles vibrate in place and move less freely.
Heat always transfers from an object with a higher temperature to one with a lower temperature until what happens?
They reach thermal equilibrium.
You leave an ice cube on the counter. Describe what happens to the temperature and the movement of particles as it melts.
Temperature increases, and the particles move faster as the solid turns into a liquid.
When two objects reach the same temperature and no more energy is transferred, what is that state called?
equilibrium.
Two gases are at the same temperature, but one has heavier particles. Which has more total kinetic energy and why?
The gas with heavier particles, because kinetic energy also depends on particle mass.
Two beakers of water are at 50°C, but one contains more water. Which has more thermal energy and why?
The beaker with more water, because it has more particles, even though the temperature is the same.
A metal spoon and a plastic spoon are left in a cup of hot soup. After a minute, the metal spoon feels hotter. Explain why.
The metal conducts heat better, so it transfers thermal energy more quickly from the soup to the spoon