Question

Assertion A : Boron is hardest element in group-13. 

Reason R : High lattice enthalpy due to strong crystalline lattice. 

(1) Both A and R are correct and R is correct explanation of Assertion 

(2) Both A and R are correct but R is not correct explanation 

(3) A is correct but R is wrong statement 

(4) Both A and R are correct

Answer 1

(1) Both A and R are correct and R is correct explanation of Assertion 

Due to very strong crystalline lattice Boron has unusually high M.P.