Inorganic stuff to learn Flashcards
ideal gas equation
pV=nRT p=pressure(Pa) V=volume(m3) n=no of moles R=gas constant(see data sheet) T=temp(K)(+273)
% uncertainty=
absolute uncertainty/measured value x100%
1st ionisation energy
the energy required to remove one mole of electrons from one mole of atoms in the gas phase
electronegativity
a measure of the ability of an atom in a molecule to attract the electrons of a shared pair to itself
making bleach
Cl2+2NaOH->NaCl+NaClO+H2O -disproportionation (NaClO=chloric (I) acid=bleach)
standard enthalpy of formation
the enthalpy change that occurs when one mole of a compound is formed from its elements in their standard states under standard conditions
standard enthalpy of combustion
the enthalpy change that occurs when one mole of a substance is completely burned in oxygen, converted to standard conditions
enthalpy change calculations
Q=mcT Q=energy(J),m=mass of water that undergoes temp change,c=specific heat capacity of water,T=temp change of water H=Q/n Q=energy(kJ),n=moles of reactant
dynamic equilibrium properties
conc. of reactants and products are constant
rate of forward and backward reactions are the same
rates: k=
rate/[A]^n[B}^m
or
ln2/half life
units of k
(moldm-3)^(1-n) s-1
n=overall order of reaction
exponential factor of Arrhenius
proportion of molecules that have sufficient energy for a reaction to take place
pre-exponential term of Arrhenius
accounts for frequency of collisions with correct orientation
Arrhenius theory
acids produce H+ in solution
bases produce OH- in solution
Bronsted-Lowry theory
acids donate a proton
bases accept proton
Lewis theory
acids accept lone pair
bases donate lone pair
pH=
-log[H+]
Relative atomic mass
The weighted mean mass of an atom of an element relative to one twelfth of the mass of an atom if carbon12
Empirical formula
The simplest whole number ratio of atoms of each element present in a compound
Molecular formula
The actual number of atoms of each element in a molecule
Atom economy
Mr of wanted product/total Mr of all products (×100%)
Structural isomerism
Same molecular formula but different structural formula
Chain, position, functional group
Stereoisomerism
Same structural formula but atoms occupy different positions in space
E/Z/cis/trans, optical
pH of weak acid
[H+]=root([HA]Ka)
Kw=
[H+][OH-]= 1x10-14moldm-3 at 25’C
pH of strong base
[H+]=Kw/[OH-]
Buffer solution made of:
weak acid and conjugate base
Methyl orange
red -> yellow, acid->alkali, 3.0-4.4
Bromothymol blue
yellow -> blue, acid -> alkali, 6.0-7.6
Phenolphthalein
colourless -> pink, acid -> alkali, 8.4-10.0
Conditions for electrodes
25’C, 100kPa, 1moldm-3
KMnO4 redox titration colour change
Purple -> colourless
KMnO4 redox titration ratio
1:5, MnO4:Fe
K2Cr2O7 redox titration colour change
Orange -> green
K2Cr2O7 redox titration ratio
1:6, Cr2O7:Fe
Colour of indicator used in K2Cr2O7 titration
violet-blue in excess K2Cr2O7
Thiosulphate redox titration colour
brown->colourless, fades
End point of thiosulphate redox
Add starch, blue black colour disappears
enthalpy & entropy equation
dS=dH/T
entropy units
JK-1mol-1
Gibb’s free energy
dG=dH-TdS
