Thermodynamics Equations

Question 1

Units for pV=nRT

Answer 1

p- pascals
V- m^3
n- moles
R- Jmol^-1K^-1
T- Kelvin

Question 2

What is Boyle’s law?

Answer 2

Pressure is inversely proportional to volume

Question 3

Under what conditions is Boyle’s law obeyed?

Answer 3

As p —> 0 and V —> infinity

Question 4

What is Charles’ Law? (Holy Roman Emperor)

Answer 4

V is directly proportional to T

Question 5

What is the Gibbs free energy equation?

Answer 5

ΔG=ΔH - TΔS

Question 6

Irreversible gas expansion equation

Answer 6

Work= -p ex • ΔV

Question 7

Isothermal reversible gas expansion

Answer 7

Work = -nRT • ln(V2/V1)

Question 8

Specific heat capacity

Answer 8

C = q/mΔT
Where q = energy transfered as heat

Question 9

The first law of thermodynamics

Answer 9

ΔU = q + w
Where U is internal energy. The sum of all potential and kinetic energies of particles in a system

Question 10

Change in enthalpy at constant pressure

Answer 10

ΔH = ΔU +pΔV

Question 11

Εntropy change

Answer 11

ΔS = q(rev)/T
dS= dq(rev)/T

Question 12

Entropy change accompanying expansion

Answer 12

ΔS = ΔH(tr)/T(tr)

Question 13

Gibbs energy equation

Answer 13

ΔG = ΔH - TΔS

Question 14

Gibbs energy change for reaction under prevailing conditions

Answer 14

ΔrG = ΔrGΘ + RTln(Q)
Reaction quotient Q can be replaced by equilibrium constant K.

Question 15

Standard reaction Gibbs energy change at a specified T

Answer 15

ΔrGΘ = ΔrHΘ - TΔrSΘ

Question 16

Van’t Hoff equation

Answer 16

ln(K2/K1) = - (ΔrHΘ)/R x (1/T2 - 1/T2)

Question 17

Trouton’s rule

Answer 17