Mention the functional group which always occurs at the terminal position of a carbon chain of an organic compound.

Which enzyme or substance is responsible for the conversion of milk into curd?

Define the term 'structural isomerism'. Explain why propane cannot exhibit this property. Draw the structures of possible isomers of butane,$C_{4}H_{10}$.

Which of the following functional groups is present in a ketone compound?

On dropping a small piece of sodium in a test tube containing carbon compound $X$ with molecular formula $C_{2}H_{6}O$,a brisk effervescence is observed and a gas $Y$ is produced. On bringing a burning splinter at the mouth of the test tube,the gas evolved burns with a pop sound. Identify $X$ and $Y$. Also,write the chemical equation for the reaction. Write the name and structure of the product formed when you heat $X$ with excess concentrated sulphuric acid.

Draw the structure of the simplest ketone.