Assertion : PbI₄ is a stable compound. Reason : Iodide stabilizes higher oxidation state.

Silicon is doped with aluminium, which are electron deficient to create holes in a semiconductor. It increases the electrical conductivity. It is often called as p-type semiconductors. Aluminium is trivalent and Silicon is tetravalent in nature. Because, when aluminum atom replaces silicon atom in three-dimensional network of silicon dioxide, the overall structure acquires a negative charge. Comprehension Based Typed Questions Passage (Ques 19 to 24) Aluminium is stable in air and water in spite of the fact that it is reactive metal. The reason is that a thin film of its oxide is formed on its