The elements X, Y, Z and J have the indicated electron configurations starting with the innermost shell. The most metallic element is :

1. X = 2, 8, 3

2. Y = 2, 8, 8

3. Z = 2, 8, 8, 1

4. j = 2, 8, 8, 7

The correct  sequence of increasing order of density is:

1. Li < K< Na < Rb < Cs

2. Li < Na < K < Rb < Cs

3. Cs < Rb < K < Na < Li

4. K < Li < Na < Rb < Cs

A common trend in both groups I and II elements in the periodic table, as the atomic number increases, is :

1. Oxidizing power increases

2. Atomic radius increases

3. Maximum valency increases

4. Reactivity with water decreases

The expected trend of change in atomic radius down the group is:

1. Continuous decrease

2. Continuous increase

3. Periodic one, an increase followed by a decrease

4. Periodic one, a decrease followed by an increase

The outer electronic configuration of Gd (Atomic no. 64) is:

1. 4f³ 5d⁵6d²

2. 4f⁸ 5d¹⁰6d²

3. 4f⁴ 5d⁴6d²

4. 4f⁷ 5d¹6s²