Which gas is produced during the process of fermentation that causes effervescence?

Buckminsterfullerene is an allotropic form of

Mention four characteristics which change with increasing molecular mass in a homologous series.

Ethene is formed when ethanol at $443\, K$ is heated with excess of concentrated sulphuric acid. What is the role of sulphuric acid in this reaction? Write the balanced chemical equation of this reaction.

What is mixed with natural rubber to obtain vulcanized rubber?

The structural formula of an ester is shown in the image. Write the structural formula of the acid and the alcohol from which it might be prepared. Name the process of formation of ester.