States of matter

Intensive properties (and examples)

Physical properties that are independent of the amount of substance present

Ex: density, color, conductivity

Extensive properties (and examples)

Characteristics that depend on the size of the sample present

Ex: mass, volume, length

Mass

Number of molecules present

Volume

How much space a given set of molecules take up

Formula for density

Density = Mass/Volume (D = M/V)

Thermal energy

The energy created from the random motion of atoms and molecules

Relationship between thermal energy and molecular movement

Increased thermal energy = increased molecular movement

Decreased thermal energy = decreased molecular movement

(Positively correlated)

The phase of a substance depends on these two conditions (and why)

• Temperature and pressure

• Increased temperature causes particles to move apart, while increased pressure causes particles to move together (and vice versa)

• The balance/tendency toward one of these conditions dictates the phase of the substance

Difference between heat and temperature

• Heat: measurement of energy generated or applied to a substance (energy in transit)

  • Extensive property, measured in calories or joules

  • increase of heat does not necessarily increase temperature

• Temperature: measurement of average energy of the molecules within a substance

  • Intensive property, measured in Kelvin/Celsius/Fahrenheit

• Heat is the transfer from the stovetop to the pot and its water, temperature is the measurement of the water

Specific heat of capacity

The amount of energy needed to increase the temperature of 1 gram of a substance by 1 degree Celsius

Phase diagram

Diagram used to graph the physical states of a substance under varying amounts of temperature and pressure

Triple point

The temperature and pressure at which a substance exists as a solid, liquid, and gasC

Critical point

The temperature and pressure above which a substances coexists in its liquid and gas states (the physical properties become identical)

Solid to liquid

Melting

Liquid to gas

Boiling (/evaporating)

Gas to liquid

Condensation

Liquid to solid

Freezing

Solid to gas

Sublimation

Gas to solid

Deposition