PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions for Chemistry

Name the reagents used in the following reactions:

Predict the products of the following reactions:

Draw the structures of major monohalo products in each of the following reactions :

Explain the term with suitable examples:

Alcosol

Explain the term with suitable examples:

Aerosol

Explain the term with suitable examples:

Hydrosol

Write a short note on the following:

Coupling reaction

Give plausible explanation for the following:

During the preparation of esters from a carboxylic acid and an alcohol in the presence of an acid catalyst, the water or the ester should be removed as soon as it is formed.

Complete the synthesis by giving missing starting material, reagent or product.

Give one example each of lyophobic sol and lyophilic sol.

What are lyophilic and lyophobic colloids ? Which of these sols can be easily coagulated on the addition of small amounts of electrolytes?

What happens when: SO₂ gas is passed through an aqueous solution Fe⁺³ salt?

Write the major products(s) in the following:

Define the following terms: Lyophilic colloid

Write a method by which lyophobic colloids can be coagulated.

Out of sulphur sol and proteins, which one form multimolecular colloids?

Why vitamin C cannot be stored in our body?

3.9 g of benzoic acid dissolved in 49 g of benzene shows a depression in freezing point of 1.62 K. Calculate the van't Hoff factor and predict the nature of solute (associated or dissociated).

(Given : Molar mass of benzoic acid = 122 g mol⁻¹, K_f for benzene = 4.9 K kg mol⁻¹)

Give reasons for the following observations: Lyophilic sol is more stable than lyophobic sol. 

Predict the products of the following reactions :