Compounds which do not show optical activity inspite of the presence of chiral carbon atoms are called meso-compounds.
The absence of optical activity in these compound is due to the presence of a plane of symmetry in their molecules. e.g. meso-tartaric acid is optically inactive.
Nucleophilicity increases down the periodic table : I – > Br – > Cl – > F –
Sublimation would be the best method because it is applicable for those organic compounds which pass directly from solid to vapour state on heating and vice versa on cooling.
In these compounds naphthalene is volatile and benzoic acid is nonvolatile due to the formation of dimer via intermolecular hydrogen bonding.
3 o C is more stable due to the stabilization of the charge by three methyl groups (or inductive effect).
It can also be explained on the basis of hyperconjugation.
Pair of optical isomerism and geometrical isomerism are able to exhibit the phenomenon of stereoisomerism because both type of isomers differ only in their orientation in space.
Only four structural isomers are possible for diphenyl methane.
Carboxylic acid is much stronger than water and alcohol.
Since the carboxylate ion after the removal of proton is stabilised by resonating structures as higher is the tendency to donate proton, stronger is the acid.
The – OH in alcohols is almost neutral.
Acetylene is also weakest acid.
Thus the correct order is RCOOH > HOH > ROH > HC CH depending upon the rate of donation of proton.
Geometrical isomers have same molecular formula but differ in the position of atoms or groups in space due to hindered rotation about a double bond.
IUPAC Name is 1-hexene-5-yne.
In steam distillation of toluene, the pressure of toluene in vapour is less than pressure of barometer, because it is carried out when a solid or liquid is insoluble in water and is volatile with steam but the impurities are non-volatile.
