ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Lols123 on May 13, 2011, 05:30:10 pm
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Hey guys
got my 2nd SAC next week. doing a prac relating to esters and hydrocarbons (chapters 9-11)
if anyone has done it, would be great if they could share how/what to study for it besides the obvious stuff in the textbook.
E.g. Errors?
Just any random stuff that my teacher may test me on :S
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Hey guys
got my 2nd SAC next week. doing a prac relating to esters and hydrocarbons (chapters 9-11)
if anyone has done it, would be great if they could share how/what to study for it besides the obvious stuff in the textbook.
E.g. Errors?
Just any random stuff that my teacher may test me on :S
look at properties of each functional group (especially esters) - intramolecular bonding and intermolecular bonding - boiling point, acidity/basicity/neutrality, reactivity, practical applications (e.g. esters smell), solubility in water...
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thanks for the reply :)
what do you mean "intramolecular bonding and intermolecular bonding "
is that just knowing about why the boiling points become higher as dispersion forces increase as a result of a larger alkly group? and how alkanes become less soluble as alkyl group grows?
is there anything else?
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thanks for the reply :)
what do you mean "intramolecular bonding and intermolecular bonding "
is that just knowing about why the boiling points become higher as dispersion forces increase as a result of a larger alkly group? and how alkanes become less soluble as alkyl group grows?
is there anything else?
when discussing properties of functional groups, I always emphasise the importance of intra- and intermolecular bonding. Intramolecular bonding essentially refers to polarity within the molecule, which determines acidity/basicity and reactivity (e.g. compare bonding in alkanes with alkenes, or alcohols with COOHs). Intermolecular bonding (i.e. how strong are disp forces and can it form dipole-dipole attractions or H bonds) will determine boiling point/volatility (application: fractional distillation), solubility in water / other solvents, results of chromatography etc. So really the intra and intermolecular bonding I think are incredibly useful in determining properties of functional groups and thus useful for comparing molecules in different homologous series.
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ohhh okay
and with the acidic/basic stuff
just the fact that carboxylic acids are weak acids and amines are weak bases?
anything that we should know beyond that?
and also just checking dipole-dipole bonds are just bonds between atoms with very contrasting electronegativities yeah?
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ohhh okay
and with the acidic/basic stuff
just the fact that carboxylic acids are weak acids and amines are weak bases?
anything that we should know beyond that?
and also just checking dipole-dipole bonds are just bonds between atoms with very contrasting electronegativities yeah?
The main ones are carboxylic weak acids and amine weak bases, yes.
dipole-dipole bonds are electrostatic attractions between MOLECULES containing atoms of contrasting electronegativities. Be very careful with terminology.