MCQ
Note : In the following questions a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : If aluminium atoms replace a few silicon atoms in three dimensional network of silicon dioxide, the overall structure acquires a negative charge.
Reason $(R)$ : Aluminium is trivalent while silicon is tetravalent.
Assertion $(A)$ : If aluminium atoms replace a few silicon atoms in three dimensional network of silicon dioxide, the overall structure acquires a negative charge.
Reason $(R)$ : Aluminium is trivalent while silicon is tetravalent.
- ✓$A$ and $R$ both are correct, and $R$ is the correct explanation of $A.$
- B$A$ and $R$ both are correct, but $R$ is not the correct explanation of $A$.
- C$A$ is true but $R$ is false.
- D$A$ and $R$ both are false.
