Question

On dropping a small piece of sodium in a test tube containing carbon compound 'X' with molecular formula C2H6O, 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 ind structure of the product formed, when you heat 'X' with excess cone. Sulphur acid.(All India - 2016)

Answer 1

Let us solve for it

Explanation:

The carbon compound is identified as : C₂H₅OH

That is ethanol .

Now when a piece of sodium is added the reaction is :

C₂H₅OH + Na --> C₂H₅ONa + H₂

The gas Y is : hydrogen gas

This hydrogen gas burns with a popping sound .

The reaction involved is :

C₂H₅OH + Na --> C₂H₅ONa + H₂

When we heat ethanol in excess of sulphuric acid , we get ethene as sulphuric acid act as dehydrating agent .

C₂H₅OH  + H₂SO₄ ---> C₂H₄

Answer 2

(i) Products:

X = CH₃CH₂OH

Y = H₂

(ii) Chemical equation:

2CH₃CH₂OH + 2Na → 2CH₃CH₂ONa + H₂

• When ethanol reacts with sodium, it produces bubbles of hydrogen with sodium ethoxide (colourless solution).
• Hydrogen is produced burns with pop sound.

(iii) Name of the product is ethene

Structure of the product is CH₂ = CH₂

• When ethanol is heated with excess concentrated sulphur acid, dehydration of ethanol takes places which gives ethene.
• The chemical equation for the reaction is given below:
• $C H_{3} C H_{2} O H \stackrel{\text { conc.H}_{2} S O_{4}}{\longrightarrow} C H_{2}=C H_{2}+H_{2} O$