Multiple Choice QuestionsWhich 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+
Short Answer TypeExplain briefly the cause of Lanthanoid contraction.
On moving in the lanthanoid series from left to right successive electrons enter into ante penultimate 4f-subshell which imparts very poor shielding effect (due to its diffused nature), hence effective nuclear charge gradually increases with increase in atomic number. That is why shrinkage is observed on moving through lanthanide series, this is known as lanthanide contraction.
Multiple Choice QuestionsAnhydrous ferric chloride is prepared by:
dissoving Fe(OH)3 in concentrated HCl
dissolving Fe(OH)3 in dilute HCl
passing dry HCl overheated iron scrap
passing dry Cl2 gas overheated iron scrap
When H2S gas is passed in a metal sulphate solution in presence of NH4OH, a white precipitate is produced. The metal is identified as:
Zn
Fe
Pb
Hg
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