An element X occurs in short period having configuration ns²np¹ . The formula and nature of its oxide are:

1. XO₃, basic

2. XO_3, acidic

3. X₂O₃, amphoteric

4. X₂O₃, basic

The outermost electronic configuration of the most electronegative element is :

1. ns²np³

2. ns²np⁴

3. ns²np⁵

4. ns²np⁶

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

Which statement is true?

1. The electronegative nature of elements increases along the period

2. The electropositive nature of elements increases along the period

3. The chemical reactivity of elements increases along the period

4. The I.E  of element decreases along the period

The most non-metallic element among the following is:

1. Be

2. B

3. Mg

4. Al

₅₈Ce is a member of which block?

1. s-block elements.

2. p-block elements.

3. d-block elements.

4. f-block elements.

The screening effect of 'd' electrons is:

1. Much less than s-electrons.

2. Much more than s-electrons.

3. Equal to s-electrons.

4. Equal to p-electrons.

Correct statement regarding transuranic elements is :

1. They have higher atomic number than uranium.

2. They are lighter than uranium.

3. They have lower atomic number than uranium.

4. They have same atomic number as uranium.

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

General electronic configuration of outermost and penultimate shell of an atom is
(n - 1)s² (n - 1) p⁶ (n - 1)d^x ns². If n = 4 and x = 5, the number of proton in the nucleus is:

1. > 25

2. < 24

3. 25

4. 30