Kinetic Molecular Theory Flashcards
What is kinetic theory of matter
Why matter exists in different states and how matter can change to the next
What does the kinetic theory of matter say?
All matter is composed of particles which have certain amount of energy which allows them to move at different speeds depending on the temperature.
There are spaces between the particles and attractive forces between particles when they come close together.
Solids
Have little energy
Vibrate in fixed positions
Atoms held closely together in pattern called a lattice
Liquid
Energy of atoms increase(more than solids). Particles move further away than that of solids
Gas
Gas particles have lots of energy. Are far away from each other. Attractive force between particles are weak.
Kinetic moleclar theory based on 6 points
- matter consists of small particles
- particles in constant state of motion
- spaces between particles
- are forces of attraction/ repulsion between particles
- greater the temp more particles move
- particles of different substances have different sizes and masses.
Brownian motion
A phenonmenon by which collodial particles are in constant random motion
Diffusion
Physical process where a substance moves form an area of high concentration to an area of low concentration.
Rate of diffusion depends on two factors
Mass of particles
(Lower the relative molecular mass of gas, the faster the gas will diffuse. )
Temperature of substance
(The higher the temperature of the gas, the faster the gas will diffuse)
Chemical change
Break bonds and make new sustance. irreversible
Physical changes
A change of substance through physical process. Reversible
Freezing
Proces where substance changes form liquid to solid
Melting
Process where substance changes from solid to liquid
Condensation
Process where substance changes from gas to liquid
Boiling
Process where substance changes form liquid to gas (takes place anywhere in the the liquid and requires a certain temperature at a certain pressure, and a continous heating source.
Evaportaion
Process where substance chnges from liquid to gas. Occurs on the surface of the liquid.
Sublimation
Process where substance changes directly from solid to gas
Depostion
Process where substance changes directly from gas ro solid
Melting point
Temp at which substance changes from solid to liquid
Freezing point
Temp at which substance changes from liquid to solid
Boiling point
Temp at which substance changes from liquid to gas
Melting and boiling points measured at …
Standard atmospheric pressure (STP)
During change of stante…(3)
Kinetic energy remains the same and therefore temp remains contant
Change in the arrangement of particles
Potential energy increases or decreases
Pressure
Amount of force exerted per unit area
READ OVER HEATING CURVE PG.9
& COOLING CURVE PG.10
How can we tell if a sunstance is pure by looking at the melting point
If the melting point is over a temperature range the substance is impure. Gradient = O if substance is pure.
When we seperate crude oil we use …
Fractional disstilation
Least dense substances boil at lower temps while the denser subtances boil at higher temperatures
Internal energy includes…
Kinetic energy, vibrational energy, rotational energy.
Temperature
Measure of average kinetic energy of the particles in a substance
Heat
Amount of energy transferred from one body to another spontaneously due to their temperature duffernece.
