Question

activity 3.13 of metal non metal of class 10

Answer 1

• physical nature: Ionic compounds are solids and are somewhat

hard because of the strong force of attraction between the positive

and negative ions. These compounds are generally brittle and

break into pieces when pressure is applied.

• Melting and Boiling points: Ionic compounds have high melting

and boiling points (see Table 3.4). This is because a considerable

amount of energy is required to break the strong inter-ionic

attraction.

• Solubility: Electrovalent compounds are generally soluble in

water and insoluble in solvents such as kerosene, petrol, etc.

• Conduction of Electricity: The conduction of electricity through

a solution involves the movement of charged particles. A solution

of an ionic compound in water contains ions, which move to the

opposite electrodes when electricity is passed through the

solution. Ionic compounds in the solid state do not conduct

electricity because movement of ions in the solid is not possible

due to their rigid structure. But ionic compounds conduct

electricity in the molten state. This is possible in the molten state

since the elecrostatic forces of attraction between the oppositely

charged ions are overcome due to the heat. Thus, the ions move

freely and conduct electricity

Answer 2

Answer:

observation

Salts of acids and bases are Hard; brittle; have a high melting point; soluble in water; insoluble in non-polar solvents like kerosene, benzene; conducts electricity.

Explanation:

Molecules of salt are closed together by the strong Ionic bond between anions and cations. This strong attraction gives a salt hard appearance, high melting and boiling point.

In water and other polar solvents, they form strong ionic bonds, so they are soluble in water. Non-polar solvents like organic solvents and kerosene do have polar bonds. A salt molecule, therefore, does not mix with such solvents. As a result, it sinks to the bottom.

In solution form molecules of salts are in ionic form. They move freely in the solution; therefore they conduct electricity.