Which of the following compound is not coloured?

• Na₂[CuCl₄]

• Na₂[CdCl₄]

• K₄[Fe(CN)₆]

• K₃[Fe(CN)₆]

122.

The electronic configuration of Cu is

• [Ne] 3s², 3p⁶, 3d⁹, 4s²

• [Ne] 3s², 3p⁶, 3d¹⁰, 4s¹

• [Ne] 3s², 3p⁶, 3d³, 3d⁹, 4s², 4p⁶

• [Ne] 3s², 3p⁶, 3d⁵, 4s², 4p⁴

Assertion: Cuprous ion (Cu⁺) is colorless whereas cupric ion (Cu²⁺) is blue in the aqueous solution.
Reason: Cuprous ion (Cu⁺) has unpaired electrons while cupric ion (Cu²⁺) does not.

• If both assertion and reason are true and reason is a correct explanation of the assertion.

• If both the assertion and reason are true but the reason is not a correct explanation of the assertion.

• If the assertion is true but the reason is false.

• If both the assertion and reason are false.

The stable bivalency of Pb and trivalencey of Bi is:

• due to d contraction in Pb and Bi

• due to relativistic contraction of the 6s orbitals of Pb and Bi, leading to inert pair effect

• due to screening effect

• due to the attainment of noble liquid configuration

A magnetic moment of 1.73 BM will be shown by one among the following

• [Cu(NH₃)₄]²⁺

• [Ni(CN)₄]^2-

• TiCl₄

• [CoCl₆]^4-

Which of the following does not give oxygen on heating?

• KClO₃

• Zn(ClO₃)₂

• K₂Cr₂O₇

• (NH₄)₂Cr₂O₇

Which ofthe following lanthanoid ions is diamagnetic?
(At. nos. Ce = 58, Sm = 62, Eu = 63, Yb= 70)

• Ce²⁺

• Sm²⁺

• Eu²⁺

• Yb²⁺

Platinum, palladium and iridium are called noble metals because:

• Alfred Nobel discovered them

• they are shining lustrous and pleasing to look at

• they are found in native state

• they are inert towards many common reagents

Cupric compounds are more stable than their cuprous counterparts in solid state. This is because

• the endothermic character of the 2nd IP of Cu is not so high

• size of Cu²⁺ is less than Cu⁺

• Cu²⁺ has stable electronic configuration as compared to Cu⁺

• the lattice energy released for cupric compounds is much higher than Cu⁺

Explain briefly the cause of Lanthanoid contraction.