Question
Chemistry Question on Organic Chemistry- Some Basic Principles and Techniques
Why is a solution of potassium hydroxide used to absorb carbon dioxide evolved during the estimation of carbon present in an organic compound?
Answer
Carbon dioxide is acidic in nature and potassium hydroxide is a strong base. Hence, carbon dioxide reacts with potassium hydroxide to form potassium carbonate and water as
2KOH+CO→K2CO3+H2O
Thus, the mass of the U-tube containing KOH increases. This increase in the mass of U-tube gives the mass of CO2produced. From its mass, the percentage of carbon in the organic compound can be estimated.