Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Chemistry

Define van’t Hoff factor.

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 :

Define the following term:

Multimolecular colloids

Calculate the amount of benzoic acid (C₆H₅COOH) required for preparing 250 mL of 0.15 M solution in methanol.

19.5 g of CH₂FCOOH is dissolved in 500 g of water. The depression in the freezing point of water observed is 1.0°C. Calculate the van’t Hoff factor and dissociation constant of fluoroacetic acid.

How are the colloidal solutions classified on the basis of physical states of the dispersed phase and dispersion medium?

Why are hydrophobic sols easily coagulated?

How are colloids classified on the basis of Physical states of components

How are colloids classified on the basis of the nature of the dispersion medium?

How are colloids classified on the basis of interaction between the dispersed phase and the dispersion medium?

How are vitamins classified? Name the vitamin responsible for the coagulation of blood.