Tertiary butyl alcohol gives tertiary butyl chloride on treatment with

How many structural isomers of alcohols are possible with the molecular formula $C_5H_{12}O$ (ignoring stereoisomers)?

Which compound has the highest boiling point?

The reaction of $C_2H_5OH$ with $H_2SO_4$ does not give

The correct order of reactivity of hydrogen halides with ethyl alcohol is

An organic liquid $A$ containing $C$,$H$,and $O$ has a pleasant odour with a boiling point of $78\ ^\circ C$. On boiling $A$ with conc. $H_2SO_4$,a colourless gas is produced which decolourises bromine water and alkaline $KMnO_4$. One mole of this gas also reacts with one mole of $H_2$. The organic liquid $A$ is: