Equations

Question 1

What is the equation for Gibb’s Free Energy change (🔺G)

Answer 1

🔺G =🔺H - T🔺S
🔺G = Gibb’s Free Energy (Joules) (or the available energy to facilitate a chemical reaction in a system at constant temperature and pressure)
🔺H = Change in enthalpy (heat) in the system (Joules)
🔺S = Change in entropy (disorder) of the system (Joules/Kelvin)

Question 2

What is the equation for the equilibrium constant (K’eq) for the reaction A + B ↔️ C + D

Answer 2

K’eq = [C][D]/[A][B]

Question 3

What is the proper equation for 🔼G

Answer 3

🔼G = 🔼G0’ + RTln{[C][D]/[A][B]}

🔼G0' = The Standard Free Energy Change (Joules)
R = The Universal Gas Constant (kJ/mol/deg)

Question 4

What is the equation for energy (E)

Answer 4

E = hc/lambda

E = energy (joules)
h = Planck's constant
lambda = wavelength
c = the speed of light

Question 5

What is the equation for absorbance

Answer 5

Absorbance = log Io/I

Io = intensity of incident light
I = intensity of transmitted light

Question 6

What is the Beer Lambert Law

Answer 6

A = molar extinction coefficient x c x l

A = Absorbance (no units)
Molar extinction coefficient (1/M.cm)
c = concentration of sample (M)
l = path length (cm)