Which of the following lanthanoid elements is regarded as the hardest?

1. Lanthanum (La)
2. Lutetium (Lu)
3. Samarium (Sm)
4. Ytterbium (Yb)

The unpaired  electron in Eu³⁺ will be the same in: 

1. Yb²⁺

2. Ho³⁺

3. Sm²⁺

4. Gd³⁺

Primary component of Mischmetal that is commonly utilised in gas lighters is:

1. Cerium 
2. Iron
3. Samarium
4. Lanthanum

The correct statement is

1. Green vitriol and blue vitriol are isomorphus

2. KMnO₄ and K₂Cr₂O₇ are coloured due to d-d transitions

3. Cu₂Cl₂ and Ag₂S are coloured

4. Upon strong heating paramagnetic gases are evolved by CuSO₄ and AgNO₃

Which is true about the ionic radius of M²⁺?

1. Ni²⁺<Cu²⁺<Zn²⁺

2. Ni²⁺>Cu²⁺>Zn²⁺

3. Cu²⁺<Ni²⁺<Zn²⁺

4. Zn²⁺<Ni²⁺<Cu²⁺

Which of the following will not give a positive chromyl chloride test?

(1) CuCl₂

(2) ZnCl₂

(3) HgCl₂

(4) NH₄Cl

Which of the following can not exist together in aqueous solution?

1. HgCl₂ and SnCl₂

2. HgCl₂ and SnCl₄

3. SnCl₄ and FeCl₃

4. SnCl₄ and PbCl₄

A substance is found to have a magnetic moment of 3.9 B.M. The ion may be 

1. Fe⁺³

2. Mn⁺²

3. Co⁺²

4. Cu⁺²

The inner transition element is not represented by the atomic
number among 59, 74, 95, 102, and 104.

1. 59

2. 95

3. 102

4. 104

Which of the following is the correct order of second ionization energy?

1. V > Cr > Mn

2. V < Cr < Mn

3. V < Cr > Mn

4. V > Cr < Mn