Equations

Question 1

Molarity

Formula

Answer 1

cA = nA/v
moles of A divided by volume

cA units - moldm-3
nA - number moles (mol)
V - volume (dm3)

Question 2

Molality

Answer 2

mA = nA / nB*MB
moles of B divided my mass

mA units - molkg-1
nB - moles B
MB - molar mass B

Question 3

Mole Fraction

Answer 3

XA = nA /Σni
unitless
moles of A divided by total moles of the system

Question 4

ΔG=
energetics of solution

Answer 4

ΔG = VΔp - SΔΤ
Volume, pressure, entropy, temperature

Question 5

Chemical Potential μ
What is μ for an ideal gas?

Answer 5

μ= δG/δnA

for ideal gas, the chemical potential is the molar Gibbs energy at constant P and T

Question 6

if the system is at EQUILLIBRIUM, what is the value of ΔrG, μΑ and μB?

Answer 6

ΔrG = 0
μΑ = μB

Question 7

ΔrG=

Answer 7

ΔrG= νBμB - νAμA
i.e the difference in chemical potentials relative to their stoichiometries

Question 8

IDEAL
dGm =

Answer 8

dGm = dμ = Vm dp
molar Gibbs = chemical potential = molar volume

Question 9

initial Gibbs Gi=

Answer 9

nA( μΑ(Τ) + RTln(P/Pstd + μB(Τ) + RTln(P/Pstd) )

Question 10

μ(T) - μstd(T)=

Answer 10

=RTln(p/pstd)

Question 11

ΔGmix =

Answer 11

ΔGmix = Gf - Gi
= nRT(XAlnXA + XBlnXb)

XB - mole fraction of B