Unit 1 - States of matter Flashcards
Three states of matter
Solid, liquid, gas
Properties of solids
- Fixed shape and volume
- Can’t be compressed
Properties of liquids
- No fixed shape - can take the shape of their container
- Fixed volume
- Can flow
- Can’t be compressed
Properties of gases
- No fixed shape - can take the shape of their container
- Do not have fixed volume - take up volume of their container
- Can flow
- Can be compressed
Particle model of solids
- Have a regular arrangement
- Are tightly packed - particles touch each other
- Particles oscillate in fixed positions
- Strong forces of attraction holding particles in place
Particle model of liquids
- Irregular arrangement
- Tightly packed particles touching each other
- Move randomly at different speeds
- Do not move far as they frequently collide with other particles
- Weaker forces of attraction than solids
Particle model of gases
- Irregular arrangement
- Move randomly at different speed - Faster than liquids
- Very weak forces of attraction compared to solids and liquids
Melting point
The temperature at which a solids changes state to a liquid
Boiling point
The temperature at which a liquid changes state to a gas
Evaporation
- Particles on the surface with the most kinetic energy escape
- Occurs at any temperature
- Rate increases as temperature rises
Solid –> Liquid
Melting
Solid –> Gas
Sublimation
Liquid –> Solid
Freezing
Liquid –> Gas
Evaporation/Boiling
Gas –> Solid
Deposition
Gas –> Liquid
Condensation
Relationship with kinetic energy and temperature
- When temperature increases, kinetic energy does and vice versa
Behavior of particles in melting
- Vibration of particles in fixed points increases
- When enough energy is inputted, particles overcome forces of attraction and move pas each other
Behavior of particles in boiling
- Particles gain energy and move faster
- Particles with enough energy overcome forces of attraction and break free from the liquid
Behavior of particles in condensation
- Gas cools and energy is removed
- Particles slow down
- Particles eventually no longer have enough energy to overcome forces of attraction
Behavior of particles in freezing
- Liquid cools, energy removed - particles slow down
- Forces of attraction pull particles into a regular arrangement
Pressure
The amount of force applied to the surface of an object over a particular unit area
Relationship with pressure and volume
- At fixed temp.
- When pressure is increased volume decreases (vice versa)
- When pressure is decreased volume increases (vice versa)
Relationship with temperature and volume
- Temperature decreases and volume decreases
- Temperature increases and volume increases
- At fixed pressure
Proportionality between pressure and volume
- Inverse proportion
- P = 1/V
- P1VI = P2V2
Unit for pressure
Pascals (Pa)
Diffusion
The net movement of particles from an area of high concentration to an area of low concentration - down a concentration gradient
Concentration gradient
The difference of concentration between two connected areas
Factors that affect rate of diffusion
- Higher temp = increased rate
- Steeper concentration gradient = increased rate
- Decreased distance = increased rate
- Decreased mass of particles = increased rate
Reason for mass of particles affecting diffusion
- Large molecules carry more mass and need more kinetic energy than smaller molecules to move the same distance
