Unit 1 (chemical changes + structure) Flashcards
U1-1-1
reduction
redox definition
gain of electrons (by a reactant)
U1-1-1
oxidation
redox definition
loss of electrons (by a reactant)
U1-1-1
oxidising agent
a substance that accepts electrons
(and oxidises another substance)
U1-1-1
reducing agent
a substance that donates electrons
(and reduces another subtance)
U1-1-3
standard solution
a solution of accurately known concentration
U1-1-3
self-indicating reaction
a reaction involving a reactant which changes colour to show the endpoint
U1-1-3
concordant titres
titres within 0.2cm³ of each other
(e.g. 17.2 and 17.4 are concordant)
U1-2-1
covalent radius
half the distance between the centres of two covalently joined atoms
U1-2-2
1st ionisation energy
is the energy required to remove one mole of electrons from one mole of free gaseous atoms
U1-2-3
electronegativity
a measure of attraction an atom has for shared electrons
U1-3-1
phosphorus
formula
P₄
U1-3-1
Sulfur
formula
S₈
U1-3-1
pure covalent bond
a bond in which bonding electrons are shared equally
also called ‘non-polar bond’
U1-3-1
polar bond
a bond in which bonding electrons are shared unequally and which has a permanent dipole
U1-3-1
δ+ and δ−
delta plus and delta minus - partial charges
U1-3-1
covalent molecular
bonding + strcuture
has a low melting/boiling point and doesn’t conduct electricity in any form.
U1-3-1
covalent network
bonding + structure
has a very high melting/boiling point and doesn’t conduct electricity in any form
U1-3-2
polar molecule
a molecule which has a permanent dipole
U1-3-3
fullerenes
molecular forms of carbon
U1-3-3
LDFs
forces of attraction between temporary dipoles and induced dipoles
U1-3-3
IMFs/vdWFs
forces (attractions) between molecules
U1-3-3
noble gases
structure
monatomic
they exist as single atoms
U1-3-4
PDPDIs
additional electrostatic forces of attraction between polar molecules
U1-3-4
Hhydrogen bonds
electrostatic forces of attraction between molecules that contain the higly polar N-H, F-H or O-H bonds
