States of Matter Chapter 3 pg. 68 – 97 Chapter 16.1 474 - 478

States of Matter Solid Particles are tightly packed Stuck to each other in a pattern Definite Shape Definite volume

States of Matter Liquid Particles are tightly packed Able to slide past each other Can flow Variable Shape Definite volume

States of Matter Gas Particles are spread out Flying all over the place Can flow Variable volume Variable Shape

Kinetic Theory Kinetic energy – energy an object has due to its motion (Kinetic means motion) Three main parts of the theory All matter is made of tiny particles These particles are in constant motion and the higher the temperature, the faster they move At the same temperature, heavier particles move slower.

Motion in Gases There are forces of attraction among particles in all matter. The constant motion of particles in a gas allows a gas to fill a container of any shape or size.

Behavior of Liquids A liquid takes the shape of its container because its particles in a liquid can flow to new locations. The volume of a liquid is constant because the forces of attraction are strong enough to keep the particles together.

Behavior of Solids Solids have definite volume and shape because the particles in a solid vibrate around fixed locations. Strong forces of attraction Vibration is repetitive back and forth Particles do not change places with neighboring atoms.

Gas Laws Pressure is F/A (N/m2) Force distributed over an area Simplified to Pa (Pascals) 1 kPa = 1000 Pa Air Pressure - 14.7 lb/in2 101.3kPa = 1 atm = 760 mm Hg = 760 torrs Collision Theory Collisions between the particles of a gas and the walls of the container cause the pressure in a closed container of gas. More collisions more pressure

Factors that affect Gas Pressure Temperature (Kinetic energy of gas particles)  higher temperature, more KE, more speed leads to more collisions Volume (Space between particles)  Lower volume, less space, more collisions can occurs Number of Particles  More particles, more collisions can occur Each assumes the other two are constant

Boyle’s Law Volume of a gas is inversely proportional to its pressure if the temperature and number of particles are constant. P1V1 = P2V2

Examples 1.00 L of a gas at standard pressure is compressed to 473 mL. What is the new pressure of the gas? (Standard P = 1 atm) Synthetic diamonds can be manufactured at pressures of 6.00 x 104 atm. If we took 2.00 liters of gas at 1.00 atm and compressed it to a pressure of 6.00 x 104 atm, what would the volume of that gas be?

The volume of the lungs is measured by the volume of air inhaled or exhaled.  If the volume of the lungs is 2.400 L during exhalation and the pressure is 101.70 KPa, and the pressure during inhalation is 101.01 KPa, what is the volume of the lungs during inhalation? 

Temperature Conversions Pg. 20 For combined gas law temperature must in Kelvin (K) No negative Kelvin temperatures K = oC + 273 oC = K - 273

Charles’s Law The volume of a gas is directly proportional to its temperature in Kelvins if the pressure and number of particles of the gas are constant. V1 = V2 T1 T2 Absolute Zero  “No Volume of Gas”

Examples A man heats a balloon in the oven. If the balloon initially has a volume of 0.4 liters and a temperature of 20 0C, what will the volume of the balloon be after he heats it to a temperature of 250 0C? How hot will a 2.3 L balloon have to get to expand to a volume of 400 L? Assume that the initial temperature of the balloon is 25 0C.

Combined Gas Law Relationship of Effect on Gas from Temperature, Volume, and Pressure P1V1 = P2V2 T1 T2 Standard Temperature and Pressure – T - 0oC, P = 1 atm

Energy and Phase Changes Energy - the ability change or move matter Measured in Joules (J) Energy is either absorbed or released during a phase change. Endothermic Change –absorbs energy Melting, Boiling, Sublimation Exothermic Change –released energy Freezing, Condensation, Deposition

Phase Changes Reversible physical Change that occurs when a substance changes from one state to another.

Phases Changes Molecules and atoms don’t change during a phase change The mass doesn’t change The volume does change During the phase change the temperature doesn’t change. Only the arrangement and attraction to molecules changes

Heating Curve

Work and Heat Heat flows spontaneously from hot objects to cold objects Temperature is the measure of how hot or cold something is to a reference point Based on Kinetic Energy (how much motion is occurring randomly by the particles inside of a substance)

Thermal Energy Thermal Energy depends on mass, temperature, and phase (solid, liquid, gas) of an object. More mass  More thermal Energy (More total kinetic energy)

Thermal Expansion Thermal expansion occurs because particles of matter tend to move farther apart as temperature increases. How thermometers work Doors in summertime Bimetallic strips (Thermostats)

Specific Heat Specific Heat  amount of heat needed to raise temperature of one gram of a material by one degree Celsius Lower Specific Heat  More its temperature increases when heat is added Material (100 kPa) Specific Heat (J/GoC) Water 4.18 Plastic 1.84 – 2.09 Air 1.01 Iron 0.449

Specific Heat Q = m x c x ∆ T Mass  grams C  specific heat (value of amount of heat needed to raise one gram by one degree Celsius) ∆ T  temperature change in Celsius

Measuring Heat Changes Calorimeter – instrument used to measure changes in thermal energy Heat flows from a hotter objects to a colder object until both reach the same temperature.