Which of the following will have the highest viscosity?

What is the product formed when phenylmagnesium bromide reacts with methanol?

What is the decreasing order of dehydration of the following compounds in the presence of conc. $H_2SO_4$?

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:$ Butan$-1-$ol has higher boiling point than ethoxyethane.
Reason $R:$ Extensive hydrogen bonding leads to stronger association of molecules.
In the light of the above statements,choose the correct answer from the options given below:

Identify the product $B$ in the following sequence of reactions:
$CH_3-CH_2-CH_2-OH$ $\xrightarrow[623 \ K]{Al_2O_3} A$ $\xrightarrow[(ii) H_2O, \Delta]{(i) conc. H_2SO_4} B$

An organic compound $X$ on treatment with acidified $K_2Cr_2O_7$ gives a compound $Y$ which reacts with $I_2$ and sodium carbonate to form tri-iodomethane. The compound $X$ is