Revision flashcards
What is a complex ion?
A central metal ion or atom surrounded by coordinately bonded ligand
What is a coordinate bond?
A dative covalent bond
What is a ligand?
An atom, ion or molecule that donates at least one lone pair of electrons to a central transition metal ion forming a dative covalent bond
A ligand must have at least 1 lone pair
1 lone pair = monodentate
2 lone pairs = bidentate
More than 2 lone pairs = polydentate
What is the coordination number?
The number of coordinate bonds
6 = octahedral
4 = tetrahedral though sometimes square planar
What are the rate constant units?
mol dm-3 s-1
What is zero order?
If [A] changes and the rate stays the same, the order of reaction with respect to [A] is zero order
What is first order?
If the [A] is proportional to the rate the order of reaction is first order
What is second order?
If the rate is proportional to [A]2 the order is second order
Overall order =
The sum of orders of all reactants
What is a reducing agent?
Are themselves oxidised
Donates electrons
What is an oxidising agent?
Are themselves reduced
Accept electrons
What is a chiral carbon?
An carbon atom which has 4 different groups
If a molecule has more than one chiral centre it has more than two optical isomers
What is an enantiomer/optical isomer?
Have a chiral carbon
Non-super imposable mirror images
They rotate around plane-polarised light which only vibrates in one direction
One enantiomer rotates in the clockwise direction and the other in the anti-clockwise
What is a pharmacophore?
The part of a drug that fits into the receptor site and makes it medicinally active
What 3 things does the fit of a pharmacophore depend on?
1) Size and shape - must be complementary to the receptor site
2) Orientation - if its shows E/Z isomerism only one of the isomers will fit
3) Bond formation - functional groups in the pharmacophore will form temporary bonds which are mostly ionic interactions or intermolecular forces
– Dipole-dipole forces in pharmacophores with polar groups
H bonding in alcohols, amines or carboxylic acids
Ionic interactions - acidic and base functional groups can donate or accept protons to become changed and form electrostatic attractions
Amines
Organic derivatives of ammonia
If one of the hydrogens in NH3 are replaced with an R group you have a primary amine
Why are amines bases?
They have a lone pair which accepts electrons to form a cation
The lone pair on the nitrogen can form a dative bond with a H+ ion
Testing for amines
Test for using damp red litmus paper which turns blue
OR
A small amount of an acyl chloride which would give of white fumes of HCl gas
How can amines be neutralised?
Using an ammonium salt
What is a salt?
A chemical compound consisting of an ionic assembly of cations and anions which results in a compound with no overall net charge
What are 3 methods of preventing rusting?
Painting/coating
Oiling/greasing
Sacrificial method -
This involved placing a more reactive metal with the iron
Galvanizing - a coating of zinc
OR blocks of zinc can be bolted to the iron
Why are transition metals transition metals?
Part filled d-orbitals
What does it mean if an atom economy is high?
The higher the atom economy the more efficient the process as less waste products are produced
How do you calculate atom economy?
Mr of desired product / sum of Mr of all reactants
x 100
Assuming the yield is 100%
The number of moles in the chemical equation count
