D and F Block

Question 1

Diff between oxidation states of Ln and Ac

Answer 1

Ln has only one stable oxidation state whereas actinoids have many

Question 2

Ce(IV) can oxidise water. True or false?

Answer 2

True

Question 3

Ln elements which show +4 oxidation state in oxides only

Answer 3

Pr, Nd, Tb, Dy

Question 4

Color of Ln compounds attributed to

Answer 4

Presence of f electrons

Question 5

Ln ionization enthalpies comparable to?

Answer 5

Ca

Question 6

E- value of Eu is

Answer 6

-2.0V

Question 7

Half life of lawrencium

Answer 7

3 minutes

Question 8

Actinoids are _____ magnetic than lanthanoids

Answer 8

Less

Question 9

MO oxides are

Answer 9

ionic

Question 10

V2O3 is _________ and V2O5 is ________

Answer 10

Basic

Amphoteric

Question 11

Color of Na2CrO4

Na2Cr2O7

Answer 11

Yellow

Orange

Question 12

Chromate in acidic solution?

Angle of dichromate?

Answer 12

Becomes dichromate

126°

Question 13

In acidic solution, Cr2O7 accepts how many electrons?

Answer 13

6

Question 14

KMnO4 is isostuctural to?

KMnO4 magnetism due to?

Answer 14

KClO4

Charge transfer transition

Question 15

KMno4 accepts electrons in
Neutral:
4H+:
8H+:

Answer 15

1
3
5

Question 16

At [H+] = 1, KMnO4 should _______ water

Answer 16

Oxidise

Question 17

Metal radii of alloy metals are within ___% of each other

Answer 17

15

Question 18

Elements passive to dilute non oxidising acids

Answer 18

Titanium, vanadium

Question 19

Ni E- value due to

Answer 19

Highest negative enthalpy of hydration

Question 20

Reason why fluorine gives highest oxidation state in
CoF3
VF5, CrF6

Answer 20

Higher lattice energy

Higher bond enthalpy