what must you include when drawing H bond diagrams?
- δ charges
- LONE PAIRS
- labelled dotted H bond (from lone pairs to charges)
why might chemical shifts not make sense?
chemical shifts vary depending on the solvent so they might be a little off what you expect
Na2CO3 + H2SO4 –>
–> Na2SO4 + H2O + CO2
how to work out the Mr of condensation polymers?
- calc Mr of monomer
- multiply by no. of monomers
- subtract H2O x (no. of monomers - 1)
(this is the no. of bonds formed therefore number of water molecules lost)
limitations of free radical substitution
- further substitution could occur
- substitution can happen anywhere along chain
- multiple unwanted products could be made by different termination steps
where is the ozone layer located?
outer stratosphere (takes time for organohalogens to reach there before reacting with ozone)
why were CFCs very stable?
C-X bonds are very strong
what does CFC stand for?
chlorofluorocarbons
why is the stability of CFCs bad?
they last a long time in the stratosphere
what must you do when writing a “molecular formula”?
- write each element ONCE only
e.g. C5H13N instead of C5H11NH2
why does a 3° amine have a lower boiling point than a 2° or 1°?
- 3° has more branching
- fewer points of contact
- weaker LDFs
- 3° cannot form H bonds (as N is in the centre of there branches) but 1° and 2° can
- H bonds are stronger than LDFs so require more energy to overcome
radical
species with an unpaired e-
when is water produced in alcohol reactions?
in the first step ONLY (if oxidation occurs twice to make a carboxylic acid, two oxygens are used but only one water is produced)
why does cis/trans or E/Z isomerism occur?
- double bond restricts rotation of the groups attached to each C in C=C bond
- two different groups attached to each C in the C=C bond (with one group in common for cis/trans)
why is excess ammonia used to make amines?
avoid making 2° or 3° amines
how many [H] are used to reduce NO2 group?
6[H]
6[H] + NO2 –> NH2 + 2H2O
why are condensation polymers more environmentally friendly than addition polymers?
- condensation polymers can be hydrolysed unlike addition polymers
- only condensation polymers are biodegradable
how can polymers be made more environmentally friendly?
make them biodegradable or photodegradable
what should you do during purification if acid has been used in organic synthesis?
neutralise excess acid with NaOH etc
two ways to test purity
- melting point
- TLC compared to pure reactants/products
