JEE Main202427 Jan 2024Morning ShiftChemistryp Block Elements (Group 13 & 14)Actual
Given below are two statements : one is labelled as Assertion ( A ) and the other is labelled as Reason ( R ) . Assertion (A) : Melting point of Boron ( 2453 K ) is unusually high in group 13 elements. Reason (R) : Solid Boron has very strong crystalline lattice. In the light of the above statements, choose the most appropriate answer from the options given below ;
Options
- ABoth (A) and (R) are correct but (R) Is not the correct explanation of (A)
- BBoth (A) and (R) are correct and (R) is the correct explanation of (A)
- C(A) is true but (R) is false
- D(A) is false but (R) is true
Correct answer
B. Both (A) and (R) are correct and (R) is the correct explanation of (A)
Step-by-step solution
Boron is non-metallic in nature. It is extremely hard and black coloured solid. Due to a very strong crystalline lattice, boron has an unusually high melting point. The rest of the members are soft metals with a low melting point and high electrical conductivity. Hence, Solid Boron has very strong crystalline lattice, so its melting point is unusually high in group 13 elements. Both (A) and (R) are correct and (R) is the correct explanation of (A)