things to memorise Flashcards
relative atomic mass
average mass of an atom compared to 1/12th of an atom of carbon-12
first ionisation energy
enthalpy change for X —> X- + e-
the minimum energy required to remove one mole of electrons from one mole of gaseous atoms
general first ionisation trends across a period
increases
number of protons increases
shielding stays the same
increased attraction between nucleus and outer electrons
deviation 1 aluminium
first electron in p-orbital
further from nucleus
higher energy
deviation 2 sulfur
pair of electrons
in p-orbital
repel each other
reasons why a sample is ionised in a mass spectrometer
acceleration
detection
4 most electronegative elements
nitrogen oxygen fluorine chlorine
oxidation
LOSS OF ELECTRONS
addition of oxygen
loss of hydrogen
reduction
GAIN OF ELECTRONS
loss of oxygen
addition of hydrogen
oxidising agents
ELECTRON ACCEPTORS
oxidise other species
are themselves reduced
reducing agents
ELECTRON DONORS
reduce other species
are themselves oxidised
oxidation state if element on it own
ZERO
oxidation stare of simple ions (atoms turned into ion)
equal to charge on ion
oxidation state of hydrogen
+1
oxidation state of oxygen
-2
oxidation state of fluorine
-1
oxidation state of chlorine
-1
what is the sum of oxidation state in a compound
ZERO
what is the sum of oxidation states in complex ions
equal to charge on ion
what are exceptions in oxidation states
- hydrogen = +1
- oxygen = -2
- fluorine = -1
- chlorine =-1
changes in oxidation number: oxidation
oxidation no. INCREASES
changes in oxidation number: reduction
oxidation no. DECREASES
balancing oxygen atoms
add H2O
balancing hydrogen atoms
add H+
balancing charges
add e-
moles =
mass (g) / Mr
1kg =
1000 g
1mg =
0.001 g
ideal gas equation
PV = nRT
empirical formula
simplest whole number ratio of atoms in a substance
molecular formula
actual no. of atoms of each element
