Section 1
Which phase change causes solid to liquid?
Melting.
Which phase change causes liquid to solid?
Freezing
Which phases change causes gas to liquid?
Condensation.
Which phase change causes liquid to gas?
Evaporation.
What is it called when a molecules freedom of movement changes levels?
Phase change.
What are the 3 states of matter?
Solid, liquid, and gas.
Which state of matter has the lowest movement?
Solid
When molecules are moving away from each other, which phase are they in?
Gas.
What happens when the temperature increases kinetic energy.
It gets colder.
What energy does an object have that causes it to move?
Kinetic Energy.
Why do two molecules stay close together in liquid and solids?
They are attracted to each other.
How do molecules move when they are in liquid form?
The move around each other.
When molecules are in the solid phase, how are they moving?
The move in place.
What is a different form or state of a substance?
Phase.
Which state of matter(s) have molecules that move???
ALL OF THEM.
(solids, liquids, and gases)
When an ice cube melts, does its energy transfer out or in?
Heat is transferred into the cube.
What happens when the temperature increases kinetic energy?
It gets hotter.
How does a puddle go away after the sun comes out?
Energy is transferred into the puddle.
What happens when you add thermal energy to an object?
They speed up.
What state of matter has the most movement?
Gas
Why do molecules slow down when you take out thermal energy from it?
The energy can no longer overcome the attraction of the molecules.
A scientist has a liquid at room temperature. He accidentally transfers energy into the liquid, but it does not change phase.
Did the movement of the molecules change?
Yes, their speed increased.
A scientist has a liquid at room temperature with a strong molecular attraction, and she wants to change its phase. Would it be easier to turn the substance into a solid or a gas?
Solid.
If Water evaporates at 100°C, but oxygen evaporates at -183°C.
Which substance has a stronger molecular attraction?
Water.
Scientists have 2 substances. Both substances are at room temperature. After transferring energy into both of the substances, "Substance 1" changed phase, but "Substance 2" did not.
Which substance has a weaker molecular attraction?
Substance 1.