Explain why ethanol is less acidic than phenol.

Explain why :

Though dimethyl ether and ethanol are isomers, still the dimethyl ether is a gas and ethanol is a liquid at room temperature.

What happens when primary, secondary and tertiary alcohols are

i) oxidised with ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ and ${\mathrm{H}}_2{\mathrm{SO}}_4$?

ii) passed over heated copper?