Structure 1.1.2- The Kinetic Molecular Theory

Question 1

Define KMT

Answer 1

a theory that explains the differences in physical properties of the 3 main states of matter (which are characterized by energy of particles)

Question 2

what does KMT posit

Answer 2

KMT posits that melting + boiling points vary based on the strength of inter-particle attraction (as a result, mp/BP vary based on temperature and pressure)

Question 3

Compare the particles of a solid, liquid, and gas (arrangement, movement, closeness)

Answer 3

Solid: repeated organized, vibrate in a fixed position, very close

liquid:randomly organized, move around each other, close

Gas:more randomly organized, move rapidly in all directions, far apart

Question 4

Define kinetic energy

Answer 4

energy of movement; temperature measures how fast particles move (hence a thermometer is a particle speedometer)

Question 5

Define the term fluid

Answer 5

fluid is an inclusive term for gases and liquid; describes substances that diffuse (spread out) in a container

Question 6

What happens to the temperature and kinetic energy as we move from s -> l ->g

Answer 6

both temp and kinetic energy increases

Question 7

What happens to the mp/BP when pressure decreases

Answer 7

it is easier for particles to seperate, hence mp/BP is lower

Question 8

What happens to the mp/BP when pressure increases

Answer 8

it is harder to seperate particles, so mp/BP is higher

Question 9

solid to liquid, and liquid to solid

Answer 9

melting , freezing

Question 10

liquid to gas, gas to liquid

Answer 10

vaporization, condensation

Question 11

solid to gas, gas to solid

Answer 11

sublimation, deposition

Question 12

what does the term vaporization include

Answer 12

boiling and evaporating

Question 13

evaporation vs boiling

Answer 13

evaporation occurs at surface of liquid at a range of temps below the boiling point

boiling occurs at fixed temperatures and pressures

Question 14

heating vs cooling curve

Answer 14

heating: temp increases as energy is added
cooling:temp decreases as energy is removed

Question 15

Y and X axis of a heating/cooling curve

Answer 15

Yaxis: temp (C)
X axis: energy added/removed (J)

Question 16

Kinetic (KE or Ek) vs Potential energy (PE or Ep)

Answer 16

Kinetic energy is the movement of particles, when this energy is present, particles change speed (and hence the temp) but distance is constant

Potential energy is not detected via a thermometer, heat is added/removed w/o temp change, and it is present when particle distance changes w/o change in speed