Glycerol is used in the manufacture of

Which of the following substances acts as a dehydrating agent for alcohols?

The reaction of allyl alcohol with $MCPBA$ ($meta$-chloroperbenzoic acid) is shown below:
Allyl alcohol $\xrightarrow{MCPBA}$ Product
What is the stereochemistry of the product of the above reaction?

The reagent used for the dehydration of an alcohol is

Dehydration of an alcohol $(A)$ gives an alkene. Ozonolysis of one molecule of this alkene yields two molecules of acetaldehyde. Identify the alcohol $(A)$.

Which of the following can be used to test the acidic nature of ethanol?