Calculations Flashcards
Speed of light =
wavelength x frequency
Energy of a photon =
planck constant x frequency
Percentage yield =
experimental yield / theoretical yield x100
Percentage uncertainty =
uncertainty / measured quantity x100
Moles (titre) =
concentration x volume
Moles (other) =
mass / Mr
Ideal Gas Equation =
pressure x volume = gas constant x temperature x number of moles
Q =
mass x specific heat capacity x change in temperature
Enthalpy change =
Q / mol
Kc =
products / reactants (to the power of moles)
Volume = (gas)
moles x 24
Density =
mass / volume
Atom economy =
formula mass of desired product / formula mass of all reactants x100
Rate of reaction =
change / time taken
Gradient =
y / x
Rate =
k [A] [B]^2
Arrhenius equation =
Rate constant = collision frequency x e -(activation enthalpy/gas constant x temperature)
lnk =
lnA -Ea/RT or -Ea/R x 1/T + lnA
Half life =
t x 1/2
E cell =
E° reduction - E° oxidation
pH of a strong acid =
-log10[H+(aq)]
pH of a weak acid =
Ka = [H+] [A-] / [HA]
pH of a strong alkali =
Kw = [H+][OH-]
pH of a buffer =
Ka = [H+] x [salt] / [acid]
Ksp =
[product][product]
Kpc =
component in stationary phase / component in mobile phase
Entropy change =
total of products - total of reactants
Total entropy change =
Change of surroundings (-enthalpy change / temperature) + change of system
ΔH =
total bonds broken - total bonds made
Volumes of gas (dm3) =
Moles x 24
Volumes of gas (cm3)
Moles x 24000
