The product formed when glycerol reacts with $PCl_5$ is -

$HO-CH_2-CH_2-OH$ on heating with periodic acid gives:

What is the correct order of reactivity of the following alcohols towards $H-X$?
$(I) \; CH_2 = CH - OH$
$(II) \; CH_2 = CH - CH_2OH$
$(III) \; CH_3 - CH_2 - OH$
$(IV) \; CH_3 - CH(OH) - CH_3$

Which of the following is $NOT$ formed when glycerol reacts with $HI$?

In the following reaction sequence,$X$ and $Y$,respectively,are:
$CH_2=C(CH_3)_2$ $\xrightarrow{X} \text{Epoxide}$ $\xrightarrow{Y} (CH_3)_3C-OH$

Which one of the following is a secondary alcohol?