MCQ
Below are two statements, one labeled as Assertion $(A)$ and the other as Reason $(R):$

Assertion $(A)$: Among group $13$ elements, boron's melting point is unusually high $(2453 \mathrm{~K})$.

Reason $(R):$ Solid boron has a strong crystalline lattice.

In the context of the above statements, choose the correct answer from the following options:

  • A
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of $A.$

     

     

  • Both $A$ and $R$ are true, but $R$ is the correct explanation of $A.$
  • C
    $A $ is true, but $R$ is false

     

  • D
    $A$ is false, but $R$ is true

     

Answer

Correct option: B.
Both $A$ and $R$ are true, but $R$ is the correct explanation of $A.$
b
Solid Boron has very strong crystalline lattice so its melting point unusually high in group $13$ elements

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