topic 4 physical behavior of matter. phases of matter the 3 phases of matter are: solid, liquid...

TOPIC 4PHYSICAL BEHAVIOR

OF MATTER

Phases of Matter

The 3 phases of matter are: solid, liquid & gas.

Heat is exchanged during heating, cooling & phase changes.

The kinetic molecular theory explains the behavior of gases.

Mixtures separate by physical means.

Phases of Matter

The solid phase contains matter held in a rigid form.

A substance in this phase has a definite volume and shape.

Strong attractive forces hold the particles together and true solids have a crystalline structure.

Phases of Matter

The liquid phase has particles that are not held together as rigidly as the solid phase.

Particles are able to move which prevents the liquids from having a definite shape but are held together with enough attractive forces to give a definite volume.

Phases of Matter

The gaseous phase has minimal attractive forces holding them together.

Gases have neither a definite shape nor a definite volume, therefore, they will spread out indefinitely unless confined.

Heating & Cooling Curves

As temperature increases, kinetic energy increases.

Heating & Cooling Curves

Melting, also known as fusion, occurs because the particles

have enough kinetic energy to break their bonds.

Heating & Cooling Curves

During melting, temperature remains constant even though heat is being added

and thus potential energy increases but since the temperature remains constant so

does the kinetic energy.

Heating & Cooling Curves

Boiling, also known as vaporization, occurs because the particles have even more

kinetic energy breaking the liquid bonds.

Heating & Cooling Curves

Kinetic energy increases during the heating of a solid, liquid and gas.

Heating & Cooling Curves

Potential energy increases and kinetic energy remains

constant during melting of a solid and the boiling of a liquid.

Heating & Cooling Curves

The reverse of boiling is condensation and the reverse of melting is

freezing.

Heating & Cooling Curves

Sublimation is when a solid changes directly to a gas

and the reverse process is called deposition.

Temperature

Temperature is a measure of the average kinetic energy of particles measured in °C or in K and heat flows from higher temperature to

lower temperature.

Temperature

K = °C + 273 (on RT)

Heat Energy

Heat is a measure of the amount of energy transfer

and is measured in calories or joules.

Heat EnergyThe amount of heat given off or absorbed can be

calculated using the formula: q = mCΔT; where q is heat measured in Joules, m is mass

measured in grams, C is specific heat measured in J/g·K, ΔT is change in temperature measured

in °C or K.

Heat Energy

The heat of fusion is the amount of heat needed to convert a

solid to liquid and the value is 334 J/g found in Table B.

Heat Energy

The heat of vaporization is the amount of heat needed to

convert a liquid to gas and the value is 2260 J/g found in Table

B.

Heat Energy

Melting and boiling are endothermic processes, requiring heat; freezing and condensation

are exothermic processes, releasing heat.

Behavior of Gases

The kinetic molecular theory is a model/theory used to

explain the behavior of gases.

Kinetic Molecular Theory Ideas

Particles are in constant, random, straight-line motion

Particles collide with each other & walls; transfer energy; no net loss

Kinetic Molecular Theory Ideas Particles separated by

great distances, therefore, volume by themselves is negligible

Particles do not attract each other

Behavior of Gases

The two elements most like a real gas are hydrogen &

helium.

Behavior of Gases

Gases are most ideal at low pressure and high

temperature.

Behavior of Gases

Avogadro’s hypothesis states that when the volume, temperature &

pressure of two gases are the same, they contain the same

number of molecules.