If a trivalent atom replaces a few silicon atoms in the three-dimensional network of silicon dioxide,what would be the type of charge on the overall structure?

Which of the following represents the lattice structure of $A_{0.95} O$ containing $A^{2+}$,$A^{3+}$,and $O^{2-}$ ions?

Due to vacancy defects,the density of a solid substance .............

Which of the following point defects are shown by $AgBr_{(s)}$ crystals?
$A$. Schottky defect
$B$. Frenkel defect
$C$. Metal excess defect
$D$. Metal deficiency defect

Non-stoichiometric cuprous oxide,$Cu_{2}O$ can be prepared in the laboratory. In this oxide,the copper to oxygen ratio is slightly less than $2:1$. Can you account for the fact that this substance is a $p$-type semiconductor?

Assertion: In an ionic solid $(MX)$,Schottky defect contains an equal number of cations and anions.
Reason: Equal number of vacancies are present for both cations and anions.