Scandium (Z = 21) is a transition element but zinc (Z = 30) is not because-

1. Sc has 3d⁰ and Zn has 3d¹⁰ 
2. Sc has 3d¹ and Zn has 3d¹⁰ 
3. Sc has 3d¹⁰ and Zn has 3d¹  
4. None of the above

The transition elements exhibit higher enthalpies of atomisation because-

The transition element that does not exhibit variable oxidation states is:

1. Mn
2. Cr
3. Sc
4. Fe

Given below are two statements: 

The correct sequence of decreasing oxidizing power of VO²⁺, MnO₄^– , Cr₂O₇^2–  is:
1. VO₂⁺ > MnO₄^– > Cr₂O₇^2–
2. MnO₄^– > Cr₂O₇^2– > VO₂⁺
3. MnO₄^– < Cr₂O₇^2– < VO₂⁺ 
4. Cr₂O₇^2– > VO₂⁺ > MnO₄^–

The magnetic moment of a divalent ion (atomic number = 25) in aqueous solution is:

1. 4.34
2. 5.92
3. 6.12
4. 4.87
 

The example of disproportionation reaction among the following is:
1. 3\(MnO_{4}^{2-}\)+ 4 H⁺ → 2\(MnO_{4}^{-}\) + MnO₂ + 2H₂O
2. Na₂Cr₂O₇ + 2 KCl → K₂Cr₂O₇ + 2 NaCl
3. PCl₅ + H₂O → POCl₃ +  2HCl
4. 2MnO₂ + 4KOH + O₂ → 2K₂MnO₄ + 2H₂O

The well known element of lanthanoid series that exhibit +4 oxidation state, is-

1. Ac
2. Ce
3. Eu
4. Yb