Amount of Substance 2 Flashcards
Ionic Equations
Write out the pererate ions for any molecule with state symbol of Aq (Aquious)
Remove any spectator ions - any ions which are the same on both sides
simplify coefficnets if possible
Percentage Yield
(actual mass / expected mass) X 100
Limiting reagent
of percentage yield
one thing that stops a reaction from taking place
Theoretical yield can change due to?
impure reactants
unwanted by products
products may be left in the beakers
Atom Economy
(mass of useful products / total mass of products) X 100
Limiting reagent
of atom economy
one with the smallest moles
Electrons fill energy levels
from centre outwards
Group Number
number of electrons in the outer orbital
Energy Levels
Shells
Period Number
number of energy levels
sub levels
within energy levels
electron orbitals
electron orbitals
hold 2 electrons
regions of space in which electrons spend most of their time
Electrons spin
opposite directions to each other
one spinds clockwise the other spinds counter clockwise
S sub level
2 electrons
P sublevel
6 electrons
D sublevel
10 electrons
F sublevels
14 electrons
orbitals fill
1s 2s 2p 3s 3p 4s 3d 4p
4s always fills before 3d
and empties
How do they fill
enter the lowest energy orbital available
In orbitals electrons prefer?
to occupy the orbitals on their own and only pair up when there are no more empty orbitals of the same energy level available
Exceptions
copper and chromium
Chromium electron structure
1s2 2s2 2p6 3s2 3p6 4s1 3d5
Copper electron structure
1s2 2s2 2p6 3s2 3p6 4s1 3d10
Ionisation Energy
energy needed to remove one mole of the outermost electrons from one mole of gaseous atoms
