8A.3 Internal Energy

Question 1

what is the potential energy of particles

Answer 1

the energy a particle has relative to its position within the structure material, or in relation to other molecules in a substance

Question 2

the potential energy of the particles is due to

Answer 2

the bonding between molecules

Question 3

what is the internal energy

Answer 3

the sum of the kinetic and potential energies of all the molecules within a given mass of a substance

Question 4

molecules dont have the same amount of

Answer 4

potential and kinetic energy

Question 5

what is the maxwell-Boltzmann Distribution

Answer 5

a mathematical function that describes the distribution of energies amongst particles at a given temp

Question 6

what are the characteristics of a m-b graph

Answer 6

1. there are no molecules with zero energy
2. only a few molecules have high energy
3. there is no maximum value for energy a molecule can have

Question 7

in molecules of the same object, their speed and their kinetic energy depend on

Answer 7

their speed varies(high speed, close to average, slow), and since all their masses are the same the Ek depends on speed

Question 8

M-b axis are

Answer 8

y - the number of molecules

x - the energy (Ek) of molecules

Question 9

A M-B graph is for one specific

Answer 9

temp

Question 10

if we increase the temp what happens to the peak in the M-B graph

Answer 10

the peak becomes smaller and shifts to the right and therefore higher energies

Question 11

what are the two ways to find the speed of molecules

Answer 11

1. the peak of the M-B graph represents the kinetic energy value with the greatest number of molecules that have that energy, so the speed corresponding to that Ek is the average speed
2. using root-mean-square-calculation with v = root(<c^2>)

Question 12

what is the rms speed

Answer 12

the square root of the arithmetic mean value of the squares of the speeds of particles in an ideal gas

Question 12

what is the rms speed

Answer 12

the square root of the arithmetic mean value of the squares of the speeds of particles in an ideal gas

Question 13

what is the formula for average kinetic energy

Answer 13

0.5m<c^2>

Question 14

what is the formula for average kinetic energy

Answer 14

0.5m<c^2>

Question 15

what is the formial tha links absolute temp with average Ek

Answer 15

1/2m<c^2> = 3/2kt

Question 16

how can you prove that the particles are stationary and Absolute zero

Answer 16

1/2m<c^2> = 3/2kt. when the temperature is zero this becomes a situation where the molecules are stationary and have to Ek, and in order for that to happen they need to have an rms speed of zero (i,e speed decrease to zero) since their mass is constant

Question 17

the fact that average Ek is proportional to temp is a

Answer 17

the assumption within the kinetic theory, this follows consistently from the ideal gas laws, but these are also founded on a set of assumptions

Question 18

learning tip

Answer 18

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