Phase Changes
What is the change from solid to liquid called?
melting
What do we call the total energy of all the particles in an object (kinetic + potential)?
What is Thermal Energy?
What is the term for the energy that must be added or removed for a substance to change phase without changing temperature?
What is Latent Heat
What phase change happens when puddles on the ground disappear on a sunny day?
What is evaporation
How many students are at La Union?
What is 342?
What is the change from liquid to gas called when it happens across the whole liquid?
Boiling
If two objects touch and one is hotter, heat flows from which to which
What is from the hotter object to the coolest object?
What is the name of the point where a liquid turns into gas at the surface, below the boiling point?
What is Evaporation
When you sweat and the sweat evaporates, does your body gain or lose thermal energy?
What is Lose thermal energy — evaporation removes heat and cools the body
What is the school mascot?
What is the name for the change from gas directly to solid?
Deposition
True or False — Thermal energy depends only on temperature, not on the number of particles.
False
Define specific heat in one sentence.
What is the amount of energy needed to raise the temperature of 1 kilogram (or 1 gram, depending on units) of a substance by 1 degree Celsius.)
Ice packs used for injuries often contain liquids that freeze around 0°C; how does freezing in the pack help keep things cold?
As the liquid freezes it releases latent heat to the surroundings; the pack stays cold because the temperature is held near the phase-change temperature while absorbing or releasing energy
What is a community tradition the school participates in every October?
What is Red Ribbon Week parade?
During which phase change does a substance release energy to its surroundings: melting or freezing
Freezing
A pot of water and an ice cube are both at 0°C. Which has more thermal energy? Explain briefly
The pot of water (if larger mass) has more thermal energy because thermal energy depends on the amount of matter; if comparing equal masses, liquid water at 0°C can have more thermal energy than ice at 0°C because of molecular arrangement/latent heat
Give the name and brief meaning of the term that describes the particle arrangement in a solid.
What is Crystalline or fixed lattice
Explain why metal feels colder than wood at the same temperature when you touch both
Metal is a better conductor, so it draws heat away from your hand faster, making it feel colder.
Name the last three principals you have had at La Union?
What is Mrs. Anguiano, Ms. Barraza and Mr. Sanchez
Explain why temperature can stay the same while a substance is changing phase even though heat is being added or removed
The added or removed energy goes into changing the arrangement of particles (breaking or forming bonds) rather than changing temperature; this is latent heat.
Describe how increasing temperature affects particle motion and how that relates to thermal energy.
Increasing temperature makes particles move faster (kinetic energy increases), which raises the object's thermal energy.
What is thermal equilibrium?
What is when two objects in contact reach the same temperature and no net heat flows between them.)
Describe a real-world situation where deposition occurs and name the solid that forms.
Frost forming on grass overnight — water vapor deposits as solid ice (frost)
Name the teacher(s) that has been here the longest at La Union?
Mrs. Saucedo, Ms. Gutierrez, Mrs. Juarez, or Mr. Gonzalez