MCQ
Given below are two statements :

Statement $I$ : Boron is extremely hard indicating its high lattice energy

Statement $II$ : Boron has highest melting and boiling point compared to its other group members.

In the light of the above statements, choose the most appropriate answer from the options given below

  • A
    Statement $I$ is incorrect but Statement $II$ is correct
  • Both Statement $I$ and Statement $II$ is correct
  • C
    Statement $I$ is correct but Statement $II$ is incorrect
  • D
    Both Statement $I$ and Statement $II$ is incorrect

Answer

Correct option: B.
Both Statement $I$ and Statement $II$ is correct
b
Boron is non- metallic in nature. It is extremely hard and black coloured solid. It exists in many allotropic forms. Due to very strong crystalline lattice, boron has unusually high melting point and boiling point.
Element $B$ $Al$ $Ga$ $In$ $TI$
Melting point $2453$ $933$ $303$ $430$ $576$
Boiling point $3923$ $2740$ $2676$ $2353$ $1730$

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