Explain how vacancies are introduced in an ionic solid when a cation of higher valence is aded as an impurity in it ?

Explain why ionic solids are hard and brittle .

Explain different magnetic properties of solids. What happens when these substances are heated ?

How do cations and anions of an ionic compound exist in its solid state?

When boron is added as impurity to silicon, the resulting material is

Read the following passage and answer the questions at the end of it. Conductivity of silicon increases if it is doped with certain other elements. Doping means introduction of small amount of impurities like phosphorus, arsenic or boron in the pure crystal. In pure silicon four valencies are used in bonding with other four adjacent silicon atoms. When a silicon crystal is doped with a group - 15 element (with five valence electrons) such as P, AsSb or Bi, the structure of the crystal lattice remains unchanged. Out of the five valence electrons of group - 15 doped element, four electrons are used in normal covalent bonding with silicon and fifth electron is delocalised and thus conducts electricity Doping a silicon crystal with a group-13 element (with three valence electron) such as B, Al, Ga or In produces a semiconductor with three electrons in dopant. The place where fourth electron is missing is called as electron vacancy or hole. If NaCl is doped with 10^(-3)" mol % " SrCl_(2) then concentration of cation vacancies is

What is valency of an atom? Explain how an atom can achieve an octet in their outermost shell and also explain how an atom can be chemically stable.

Explain different magnetic properties of solids. What happens when these substances are heated?

What happens to the pH of acetic acid when aqueous sodium acetate is added to it ? Explain.

Read the following passage and answer the questions at the end of it. Conductivity of silicon increases if it is doped with certain other elements. Doping means introduction of small amount of impurities like phosphorus, arsenic or boron in the pure crystal. In pure silicon four valencies are used in bonding with other four adjacent silicon atoms. When a silicon crystal is doped with a group - 15 element (with five valence electrons) such as P, AsSb or Bi, the structure of the crystal lattice remains unchanged. Out of the five valence electrons of group - 15 doped element, four electrons are used in normal covalent bonding with silicon and fifth electron is delocalised and thus conducts electricity Doping a silicon crystal with a group-13 element (with three valence electron) such as B, Al, Ga or In produces a semiconductor with three electrons in dopant. The place where fourth electron is missing is called as electron vacancy or hole. Silicon that has been doped with group - 15 elements is called