Question

Question 12.30 Why is a solution of potassium hydroxide used to absorb carbon dioxide evolved during the estimation of carbon present in an organic compound?

Class XI Organic Chemistry : Some Basic Principles and Techniques Page 364

Answer 1

Hi

Here is your answer,

CO₂ is slightly acidic in nature, therefore, it reacts with the strong base KOH to form K₂CO₃ and from the weight of the CO₂ obtained, percentage of carbon in the organic compound is calculated

                      2KOH + CO₂ -----> K₂CO₃ + H₂O

The increase in the weight of U-tube containing KOH gives the weight CO₂ produced and from the weight of the CO₂ obtained, percentage

           %C = 12/44 × weight of CO₂ formed/ weight of the substance taken ×100

Answer 2

As you know,
CO2 is slightly acidic in nature , therefore it reacts with strong base KOH to form K2CO3 and form the weight of CO2 obtained , the percentage of Carbon in the organic compound is calculated .

2KOH + CO2 ----> K2CO3 + H2O

Increases in the weight of U-tube containing KOH gives the weight of CO2 produced and form the weight of the CO2 obtained ,

So, % of Carbon in the organic compound is calculated as

% of Carbon = (12/44) × {mass of CO2 formed/mass of substance taken} × 100