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

Relative lowering of vapour pressure is a colligative property because:

(i) It depends on the concentration of a non electrolyte solute in solution and does not depend on the nature of the solute molecules.

(ii) It depends on number of particles of electrolyte solute in solution and does not depend on the nature of the solute particles.

(iii) It depends on the concentration of a non electrolyte solute in solution as well as on the nature of the solute molecules.

(iv) It depends on the concentration of an electrolyte or nonelectrolyte solute in solution as well as on the nature of solute molecules.

Freshly prepared precipitate sometimes gets converted to colloidal solution by ______.

Which of the following electrolytes will have maximum coagulating value for AgI/Ag⁺ solution?

A colloidal system having a solid substance as a dispersed phase and a liquid as a dispersion medium is classified as ______.

Which of the following process is responsible for the formation of delta at a place where rivers meet the sea?

An emulsion cannot be broken by:

(i) heating

(ii) adding more amount of dispersion medium

(iii) freezing

(iv) adding emulsifying agent

Which of the following substances will precipitate the negatively charged emulsions?

(i) \[\ce{KCl}\]

(ii) glucose

(iii) urea

(iv) \[\ce{NaCl}\]

Gelatin which is a peptide is added in icecreams. What can be its role?

What is collodion?

What happens when electric field is applied to colloidal solution?

A colloid is formed by adding \[\ce{FeCl3}\] in excess of hot water. What will happen if excess sodium chloride is added to this colloid?

How do emulsifying agents stabilise the emulsion?

Why are some medicines more effective in the colloidal form?

How does the precipitation of colloidal smoke take place in Cottrell precipitator?

On the basis of Hardy-Schulze rule explain why the coagulating power of phosphate is higher than chloride.

Why does bleeding stop by rubbing moist alum?

Why is \[\ce{Fe(OH)3}\] colloid positively charged, when prepared by adding \[\ce{FeCl3}\] to hot water?

Match the items of Column I and Column II.

Match the items of Column I with items of Column II and assign the correct code:

Gadolinium belongs to 4f series. It’s atomic number is 64. Which of the following is the correct electronic configuration of gadolinium?