physical Flashcards
(19 cards)
equation with potassium manganate and iron in the titration redox question
MnO4− + 5Fe2+ + 8H+→Mn2+ +5Fe 3+ +4H2O
basically from moles of MnO4 to Fe x5
depletion of ozone layer
O3 + O —–> 202
(Cl radical + O3 —-> ClO radical + O2
ClO radical + O —–> Cl radical + O2)
reasons why kekule was wrong
1) carbon-carbon bond lengths
- somewhat between the length of a carbon to carbon double bond and C-C.
2) hydrogenation enthalpy
- the actual hydrogenation of benzene is less negative/exothermic than expected as it is more stable
3) lack of reactivity of benzene
- benzene does not decolourise bromine water
- benzene does not undergo electrophillic addition
what is the enthalpy change of solution
the enthalpy change that takes place when one mole of a solute dissolves in a solvent
what is the average bond enthalpy
the energy required to break one mole of bonds in a gaseous molecule.
what are the two factors of lattice enthalpy
which is more significant
Ionic charge - more important
Ionic size (radius)
how does ionic charge affect lattice enthalpy
the greater the ionic charge the more negative the lattice enthalpy
-increased electrostatic attraction between ions
what are the names of the two bidentate ligands?
ethanediote
1,2-diaminothane
Gibbs equation and units
△G=△H - T△S
△G=KJ
△H=KJ
△S=J
how to find the gradient of a line
y2-y1/x2-x1
always just put back into numworks to check line is the same
units of Arrhenius
Ea is in joules per K
R is joules per K
T is kelvin
basically everything is just JOULES
definition of ionisation energy
the energy required to remove one mole of electrons from one mole of gaseous atoms to form one mole of gaseous ions
example of Cis/Trans isomerism in transition metals
Pt(NH3)2(Cl)2
example of optical isomerism in transition metals
[Ni(NH3)6]2+
definition of optical isomerism
isomers that are 2 non-superimposable mirror images of each other
when to use starch as an indicator and colour change
testing for iodine
blue/black to colourless
what to always check when balancing an equation
charges!
number of elements on each side!
how to work out the rate constant k
ln2/half life
equation for initial rate and time
initial rate is proportional to 1/t
t is time taken for solution to turn black from colourless with iodine clock
