A) 14 elements in the sixth period (atomic no. = 58 to 71) that are filling 4f sublevel
B) 14 elements in the seventh period (atomic no. = 58 to 71) that are filling 4f sublevel
C) 14 elements in the sixth period (atomic no. = 90 to 103) that are filling 4f sublevel
D) 14 elements in the seventh period (atomic no. = 90 to 103) that are filling 4f sublevel
Correct Answer: A
Solution :
As sixth period can accommodate only 18 element in the table, 14 member of HF series (atomic number 58 ot 71) are separately accommodated in a horizontal row below the periodic table. These are called as lanthanides.
You need to login to perform this action.
You will be redirected in
3 sec
