1st Law Of Thermodynamics

Question 1

What is the value of q in a reversible isothermal process?

Answer 1

q = -w = nRT ln(Vf/Vi)

Question 2

What is the value of q in an irreversible isothermal process?

Answer 2

q = -w = P_extΔV

Question 3

What is the value of ΔH in an irreversible isothermal process?

Answer 3

0

Question 4

What is the value of ΔH in a reversible isothermal process?

Answer 4

0

Question 5

What is the value of ΔU in an irreversible isothermal process?

Answer 5

0

Question 6

What is the value of ΔU in a reversible isothermal process?

Answer 6

0

Question 7

What is the value of ΔH in an isobaric process?

Answer 7

ΔH = q_p = nC_pΔT

Question 8

What is the value of work, w, in an isobaric process?

Answer 8

w = -P_extΔV

Question 9

What state function is heat equal to in an isobaric process?

Answer 9

ΔH, change in enthalpy

Question 10

What is the value of work, w, in an isochoric process?

Answer 10

0

Question 11

What is the value of heat, q, in an isochoric process?

Answer 11

q = q_v = nC_vΔT

Question 12

What state function is equal to heat, q, in an isochoric process?

Answer 12

ΔU, change in internal energy

Question 13

What is the value of ΔU in an isochoric process?

Answer 13

q_v = nC_vΔT

Question 14

What is constant in an isobaric process?

Answer 14

P (bar in isobar = pressure)

Question 15

What is constant in an isochoric process?

Answer 15

V, volume

Question 16

What necessary condition consitutes a process to be adiabatic?

Answer 16

no heat flow, q = 0

Question 17

What is the relationship between the molar heat capacities, C_p,m and C_v,m?

Answer 17

C_p,m - C_v,m = R

Question 18

For monoatomic gases, what is the value of C_v,m?

Answer 18

3/2 R (3 degrees of freedom due to translational motion)

Question 19

For diatomic gases, what is the value of C_v,m?

Answer 19

5/2 R (5 degrees of freedom: 3 - translational; 2 - rotational)

Question 20

Where is the change in internal energy, ΔU, equal to in an adiabatic process?

Answer 20

ΔU = w