f block

Question 1

last electron enters to(f block)?

Answer 1

[(n-2)f]

Question 2

no.of orbitals contained by f subshell?

Answer 2

7

Question 3

general outermost electronic configuration and its 3 valence subshells?

Answer 3

[noble gas] (n-2)f^1-14 (n-1)d^0 or1 ns^2

• (n-2)f,(n-2)d,ns

Question 4

why f block elements are known as inner transition elements/metals?

Answer 4

since in f block elements a transition within the transition occurs.

Question 5

rare earth is also known as….

Answer 5

lanthanoids

Question 6

La(57) and f block elements following it is from which grp and which period?

Answer 6

3rd group and 6th period

Question 7

after La(57)…..third grp ki EC

Answer 7

Ce(58)………Lu(71)
……….1-14 0 or 1 2
[Xe]4f 5d 6s

Question 8

what are actinones/actinoids?

Answer 8

14 elements coming after Ac(89)

Th(90)……………Lr(103)

Question 9

general EC of actionoids?

Answer 9

………..1-14 0 or 1 2
[Rn] 5f 6d 7s

Question 10

actionoids belongs to?

Answer 10

7th period and 3rd grp

Question 11

which is the only radioactive lanthanoid?

Answer 11

Promethium (Pm) 61

Question 12

most of the actinoids are…

Answer 12

radioactive

Question 13

non radioactive actinoids are?

Answer 13

Th(90) , Pa(91) , U(92)

Question 14

11 elements are known as trans uranium elements/man-made elements/synthetic elements.which are they?

Answer 14

they are actinoids. from Np(93) to Lr(103).
Np,Pu,Am,Cm,Bk,Cf,Es,Fm,Md,No,Lr.

Question 15

ec of La

Answer 15

……….1 2
[Xe]5d 6s

Question 16

EC of Ce(58)

Answer 16

………..1 1 2
[Xe] 4f 5d 6s

Question 17

EC of Gd(64)

Answer 17

………7 1 2
[Xe]4f 5d 6s

Question 18

who have 8 unpaired electron?

Answer 18

Gd

Question 19

Lu(71)

Answer 19

………14 1 2
[Xe]4f 5d 6s

Question 20

Tm(69)

Answer 20

thulium
……… 13 2
[Xe]4f 6s

Question 21

most abundant lanthanoid

Answer 21

Ce(58)

Question 22

who have high ionisation enthalpy among lanthanoid and actinoid?

Answer 22

lanthanoid

Question 23

magnetic moment of lanthanoids have contributions from..

Answer 23

spin magnetic moment and orbital magnetic moment

Question 24

who have the highest magnetic moment?

Answer 24

Nd(60)
[xe] 4f(4) 6s(2)

Question 25

mag.moment of Ln is contrubuted by?

Answer 25

spin mag.moment

Question 26

who have higher effective nuclear charge?why?

Answer 26

actinoids.
since nuclear-electron attraction is greater and atomic/ionic radius is smaller.e/m ratio of actinoids is higher.

Question 27

actinoids form stable complexes with…

Answer 27

EDTA , diketones, oxine and with pi acceptor acide ligands(CO)

Question 28

lanthanoid contraction

Answer 28

due to poor shielding effect of 4f (La to Lu)

Question 29

certain pair of elements( in 2nd and 3rd transition series) have similar atomic and ionic radii and so similar chemical properties and always occur together in nature

Answer 29

Zr(160pm)
Hf (159 pm)