d & f Block Elements

d & f Block Elements
Class:XII / Unit:8

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

Ce₂⁺
Sm₂⁺
Eu₂⁺
Yb₂⁺

2. Which of the following statements about the interstitial compounds is incorrect?

They have higher melting points than the pure metal
They are chemically reactive
They are much harder than the pure metal
They retain metallic conductivity

3. All the metals form oxides of the type MO except

Cu
Ba
Ag
Pb

4. Among the following, the coloured compound is

CuCl
[Cu(CH₃CN)]BF₄
K₃ [Cu(CN)₄]
CuF₂

5. Anhydrous ferric chloride is prepared by

Passing dry HCl over heated iron scrap
Dissolving Fe(OH)₃ in dilute HCl
Passing dry Cl₂ gas over heated iron scrap
Dissolving Fe(OH)₃ in concentrated HCl

6. How many ‘d’ electrons are in present Cr²⁺ ion

3
4
5
6

7. Cyanide process is used for extraction of

Ag
Ni
Pt
Zn

8. Identify the ore not containing iron

limonite
carnallite
siderite
chalcopyrites

9. During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’ These are

Ag and Au
Fe and Ni
Pb and Zn
Sn and Ag

10. Extraction for zinc blende is achieved by

roasting followed by reduction with another metal
electrolytic reduction
roasting followed by self reduction
roasting followed by reduction with carbon