(a) Write the formula of reagents used in the following reactions:
(i) Bromination of phenol to 2, 4,6-tribromophenol
(ii) Hydroboration of propene and then oxidation to propanol.
(b) Arrange the following compound groups in the increasing order of their property indicated.
(i) p-nitrophenol, ethanol, phenol (acidic character)
(ii) Propanol, Propane, Propanal (boiling point)
(c) Write the mechanism (using curved arrow notation) of the following reaction:
`CH_(3) - CH_(2) - overset(+)(O)H_(2) overset(CH_(3) CH_(2) OH)rarr CH_(3) - CH_(2) - underset(H)underset(|)overset(+)(O) - CH_(2) - CH_(3) + H_(2)O`

Explanation

(a) (i) Bromine water `(Br_(2)//H_(2)O)`
(ii) `B_(2)H_(6)` (diborane) for Hydroboration and `H_(2)O_(2)//OH^(-), H_(2)O` for oxidation to propanol.
(b) (i) p-nitrophenol `gt` Phenol `gt` Ethanol (acidic character)
(ii) Propanol `gt` Propanal `gt` Propane (boiling point)
(c) `CH_(3) - CH_(2) - overset(o+)(O)H_(2) overset(CH_(3)CH_(2) OH)rarr CH_(3)CH_(2) - underset(H)underset(|)overset(o+)(O) - CH_(2)CH_(3) + H_(2)O`
Mechanism