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