Classification of Elements and Periodicity in Properties — Chemistry STD 11 Science — Question

1. 3, 33, 53, 87

4. 9, 35, 51, 88

Explanation:

Elements of 5 and p-block elements are called representative elements. Elements of f-block (Z = 21 - 30, 39 48, 57 and 72 - 80, 89 and 104 - 112) are called transition elements while those of f-block (with Z = 58 - 71 and Z = 90 - 103) are called inner transition elements.

1. 3 – Group 1, 33 – group 15, 53 – group 17 and 87 – group 1.

4. 9 – Group 17, 35 – Group 17, 51 – Group 15, 88 – Group 2.​​​​​​​