(a) On dropping a small piece of sodium in an organic compound 'A' with molecular formula `C_(2)H_(6)O` in a test tube, a brisk effervescence is observed. On bringing a burning splinter, the gas evolved burns with a pop sound. Identify 'A' and write the chemical equation.
(b) What will happen when you heat the organic compound 'A' at 443 K with excess of concentrated sulphuric acid?

Explanation

(a) The available information suggests that the organic compound with molecular formula `C_(2)H_(6)O` is ethanol. It reacts with sodium metal to evolve hydrogen gas which is evolved with a brisk effervescence and burns with a pop sound.
`underset(C_(2)H_(6)O(A))(2C_(2)H_(5)OH+2Na)tounderset("Sod. ethoxide")(2C_(2)H_(5)ONa)+H_(2)`
(b) Upon heating compound 'A' at 443 K with excess of concentrated sulphuric acid, ethene gas evolves.
The reaction is known as acidic dehydration.
`underset("Ethanol")(C_(2)H_(5)OH)underset(443K)overset(H_(2)SO_(4)(conc))tounderset("Ethane")(CH_(2))=CH_(2)+H_(2)O`