Section 1 - Pgs 1-2 Flashcards
What are the 3 states of matter?
- Solid
- Liquid
- Gas
What decides which state a material is in?
How strong the forces of attraction between the particles are.
What factors affect the strength of the forces between particles in a material (and therefore its state)?
1) Material
2) Temperature
3) Pressure
How are particles arranged in a solid and why?
- Close together
- Fixed positions, but vibrate on the spot
- Lattice arrangement
This is due to strong forces of attraction between particles.
How do particles in a solid move?
They are fixed in position, but vibrate on the spot.
How do solids behave as material?
- Keep a definite shape and volume
- Cannot be compressed
How are particles arranged in a liquid and why?
- Randomly arranged
- Free to move past each other with random motion
- Usually stay close together
This is due to weak forces of attraction between particles.
How do liquids behave as a material?
- Keep a definite volume
- No definite shape -> Flow to fill bottom of a container
How do particles move in a liquid?
Constantly with random motion.
How are particles arranged in a gas and why?
- Far apart
- Free to move with random motion
- No fixed formation
This is due to very weak forces of attraction between particles.
How do gases behave as a material?
- No definite shape or volume
- Always fill any container
How do particles move in a gas?
Constantly in straight lines with random motion.
What is melting?
The change from solid to liquid (by supplying energy).
What is freezing?
The change from liquid to solid (as energy is given out).
What is evaporation?
The change from liquid to gas (by supplying energy).
What is condensation?
The change from gas to liquid (as energy is given out).
What is sublimation?
The change straight from solid to gas (by supplying energy).
What happens when a solid is heated?
- Particles gain energy and vibrate more
- This weakens the forces between particles and the solid expands
- At a certain temperature, particles have enough energy to break free from their positions
- This is called melting
What happens when a liquid is heated?
- Particles gain energy and move faster
- This weakens the forces holding the liquid together and the liquid expands
- Eventually, some particles have enough energy to break from the liquid and become a gas
- This is called evaporation/boiling
Do particles always have kinetic energy?
Yes, above -273*C (absolute zero) they do.
What is the difference between evaporation and boiling?
Evaporation - The change from liquid to gas below the boiling point of the material and only on the surface.
Boiling - The change from liquid to gas above the boiling point of the material and throughout the liquid.
In terms of states of matter, what are bonds?
Forces which hold particles together in a solid or liquid.
What happens to the temperature of a liquid when evaporation happens and why?
The kinetic energy (and therefore, temperature) decreases because only the particles with the most kinetic energy escape the liquid.
What happens to the temperature of a material when it is heated to its melting or boiling point and why?
The temperature stops increasing because all of the energy is being used to break bonds in the material.