general Flashcards
enthalpy of formation
enthalpy when one mole of a compound is formed from its reactants in std states under std conditions
enthalpy of combustion
enthalpy when one mole of a compund in it’s std state is combusted in excess oxygen under std conditions
enthalpy of atomisation
enthalpy when one mole of gaseous atoms is formed from the element in its standard state, under standard conditions.
enthalpy of hydration
the enthalpy change when one mole of gaseous ions is dissolved in water to form one mole of aqueous ions under std conditions. * ALMOST ALWAYS -tive
Factors linked to enthalpy of hyd
charge (bigger = greater) + size (smaller = greater )
enthalpy of solution
when one mole of a compound is dissolved in water to form aqueous ions under std conditions
lattice formation enthalpy
The enthalpy change when one mole of a solid ionic compound is formed from its gaseous ions under std conditions.
Gibbs eqn units: ΔG = ΔH - TΔS
ΔG = Jmol-1
ΔH = kJmol-1
* usually need to convert either
T = K
ΔS = J K-1 mol-1
heterogenous catalyst
reactants + products r in diff phases
eqn for k using half life
k = ln2/half life
dissociation + Ka eqn for weak acids
HA >< H+(aq) + A-(aq)
Ka = ([H+][A-])/[HA]
if assuming [H+] = [A-] can make:
Ka = [H+]²/[HA]
[H+ ] = √(Ka x [HA])
in conjugate base pair
ALP - acids lose protons (+ accept e-)
BAP - bases accept protons (+ lose e-)
depletion of ozone using cl
O3 + Cl –> ClO+ O2
ClO + O3 –> Cl + 2O2
therefore 2O3 –> 3O2
arrhenius
k=Ae^−Ea/RT
rearranges to: ln k=−Ea/RT + lnA
why is a buffer solution formed
acid in excess + salt produced
