Science (English Medium) Class 12 - CBSE Question Bank Solutions

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.

Write one difference between Multimolecular colloid and Macromolecular colloid

Write one difference between Sol and Gel

Write one difference between O/W emulsion and W/O emulsion

What happens when conc. is H₂SO₄ added to Cu? Write the equations.

What happens when SO₃ is passed through water? Write the equations.

Write one difference in Lyophobic sol and Lyophilic sol

Draw the structure of the following:

H₂S₂O₇

Illustrate the following reactions giving suitable example in each case 

Coupling reaction

Draw the structures of the following :

H₂S2O₇

Which of the two components of starch is water soluble?

Give one example each of sol and gel.

Write equations of the following reactions:
Coupling reaction

An unripe mango placed in a concentrated salt solution to prepare pickle, shrivels because ______.

Consider the figure and mark the correct option.

Water retention or puffiness due to high salt intake occurs due to ______.

Why are aquatic species more comfortable in cold water in comparison to warm water?

When kept in water, raisin swells in size. Name and explain the phenomenon involved with the help of a diagram. Give three applications of the phenomenon.

How will you distinguish between dispersed phase and dispersion medium in an emulsion?