In the II period, the most acidic oxide is formed by:

1. F

2. N

3. O

4. Li

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

(1) 4f³ 5d⁵6d²

(2) 4f⁸ 5d¹⁰6d²

(3) 4f⁴ 5d⁴6d²

(4) 4f⁷ 5d¹6s²

Which of the following transition metal ions has the lowest density?

(a) Copper

(b) Nickel

(c) Scandium

(d) Zinc

Ionic radii are :

(1) Inversely proportional to effective nuclear charge.

(2) Inversely proportional to square of effective nuclear charge.

(3) Directly proportional to effective nuclear charge.

(4) Directly proportional to square of effective nuclear charge.

Which one is a metalloid?

(1)Tin

(2)Germanium

(3)Sulphur

(4)Carbon

Elements with electronic configuration 1s²,2s²2p⁶, 3s²3p⁶3d¹⁰, 4s²4p⁶4d¹⁰, 5s²5p³ belongs to the ...... group of periodic table.

1. 3^rd

2. 15^th

3. 17^th

4. 12^th

General electronic configuration of the transition elements is given by:

(1) ns²nd^1-10

(2) ns²np⁶nd^1-10

(3) (n-1)d^1-10np⁶

(4) (n-1)${\mathrm{d}}^{1-10}$n$s^{1-2}$

Which of the following is not a metal?

(1) Gold

(2) mercury

(3) Scandium

(4) Selenium

The alkali metals have:

1. Highest ionization energy

2. Largest atomic radii

3. Highest density

4. Highest electronegativity

Which of the following statement is correct with respect to the property of elements with increase in atomic number in carbon family.

(1) Their metallic character decreases

(2) The stability of +2 oxidation state increases

(3) Their ionisation energy increases

(4) Their atomic size decreases