Cerium(Z=58) is an important member of lanthanoids. Which of the following statements about cerium is incorrect

(A) The common oxidation states of cerium are +3 and +4.

(B) Cerium (IV) acts as an oxidising agent

(C) The +4 oxidation state of cerium is not known in solutions

(D) The +3 oxidation state of cerium is more stable than the +4 oxidation state.

Which of the following lanthanoid has highest tendency to form complexes?

(1) Ce⁺³

(2) Pm⁺²

(3) Lu⁺³

(4) Eu⁺²

Choose the correct statement regarding bonding in AlCl₃ at high temperatures?

(I) It contains 2c-2e- bond

(II) It contains 3c-4e- bond

(III) It contains co-ordinate bond

(1) (I), (II)

(2)  (II)

(3) (II), (III)

(4) (I), (II) & (III)

The incorrect statement about Re-Re bonding in [Re₂X₈]^2- is

(1) Re-Re bond length is abnormally short

(2) Re-Re bond is comprised of one $\mathrm{\sigma }, \mathrm{two} \mathrm{\pi } \mathrm{and} \mathrm{one} \mathrm{\delta } \mathrm{bond}$

(3) If Re-Re bond points along z-axis, then square planar ReX₄ unit will use s, p_x, p_y and d_x²-y² orbitals for the formation of four Re-X $\mathrm{\sigma }$ bonds

(4) d_xy orbitals will overlap to form $\mathrm{\delta }$-bond

While Fe³⁺ is stable, Mn³⁺ is not stable in acidic solution because

(1) O₂ oxidises Mn²⁺ to Mn³⁺

(2) O₂ oxidises both Mn⁺² to Mn⁺³ and Fe²⁺ to Fe³⁺

(3) Fe³⁺ oxidises H₂O to O₂

(4) Mn^{3+ o}xidises H₂O to O₂

When dimethyl glyoxime is subjected to reflux with pure nickel sheet pieces in an appropriate solvent for 10 minutes, what is the outcome?

(1) Red precipitate

(2) Blue precipitate

(3) Yellow precipitate

(4) No precipitate

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

Which of the following atomic numbers is not the atomic number of the inner transition element: 29, 59, 74, 95, 102, 104?

(1) 59

(2) 95

(3) 102

(4) 104

When an excess of KCN is added to a solution of CuSO₄, the final product obtained is :

1. K₂[Cu(CN)₄]

2. K₃[Cu(CN)₄]

3. CuCN

4. K[Cu(CN)₂]

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