Some Basic Concepts of Organic Chemistry

These two are non-superimposable mirror images of each other, so they are enantiomers.

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 $ \equiv $ CH

depending upon the rate of donation of proton.

IUPAC Name is 1-hexene-5-yne.

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.

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.

Presence of electron withdrawing groups (– NO₂, –X, – CN) increase the acidity of phenols while the presence of electron releasing groups (– NH₂, – CH₃) decrease the acidity of phenols. This explains the following order of acidity.

p-nitrophenol > phenol > p-cresol.

Organic compounds exhibit the property of enantiomerism (optical isomerism) only when their molecules are chiral. Most chiral compounds have a chiral centre, which is an atom bonded to four different atoms or groups.
2,3-Dimethylpentane has one chiral C-atom and do not have any symmetric element.