Benzaldehyde can be converted to benzyl alcohol in concentrated aqueous $NaOH$ solution using

An ester $(A)$ with molecular formula $C_9H_{10}O_2$ was treated with excess of $CH_3MgBr$ and the complex so formed was treated with $H_2SO_4$ to give an olefin $(B)$. Ozonolysis of $(B)$ gave a ketone with molecular formula $C_8H_8O$ which shows positive iodoform test. The structure of $(A)$ is

Pyrolysis of acetone gives $CH_2=C=O$ called

In the reaction sequence,
$Cyclohex-2-en-1-one \xrightarrow[(ii) H_2O/H^+]{(i) CH_3MgBr/CuCl} (X)$
Product $(X)$ will be:

Which of the following ketones has the maximum dipole moment?

Dimethyl ketones are usually characterized through