Distinction between primary,secondary and tertiary alcohol is done by

Which of the following is not the product of dehydration of the given alcohol?

An alcohol $X$ $(C_4H_{10}O)$ on dehydration gives an alkene $(C_4H_8)$ as the major product,which on bromination followed by treatment with $Y$ gives an alkyne $C_4H_6$. The alkyne $C_4H_6$ does not react with sodium metal. What are $X$ and $Y$?

What is the product of the reaction between phenylmagnesium bromide and methanol?

When ethyl alcohol is heated with red phosphorus and $HI$,then which of the following is formed?

Which of the following statements about glycerol is incorrect?