Question

please someone tell me the trick to learn f block elements

Answer 1

Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), and Samarium (Sm)

 Celina aur Priety Ne dande se Pammy aur Simmy ko mara.

2.      Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), and Holmium (Ho)

Mnemonic for Lanthanides Part 2: Europe G(d)aya to TB(b) aur Di(y)arrohoea Ho gaya.

Europe Gaya to TB aur Diarrohoea Ho gaya.

3.      Erbium (Er), Thulium (Tm), Ytterbium (Yb) and Lutetium (Lu)

 E re, dekh Tamatar Yellow aur bLue hain.

Hope this helps.....

Answer 2

The elements in which differentiating electron enters into anti penultimate (n-2f)sub shell are called f-block elements.
These elements are placed at the bottom of periodic table.
It has two series and each series has 14 elements.
4f- series : from Cerium [z=58] to lutetium [z=71] . The elements are called as Lanthanides or rare earth metals.

Lathanide series :
Ce  Pr  Nd   Pm Sm  Eu Gd Tb Dy Ho  Er Tm Yb Lu
 
Trick; There are many tricks to remember but i generally use this trick while teaching my students
This series has 3 parts:
1st part :
Ce                Pr           Nd       Pm     Sm  
 Cita  (aur ) Preeti     Ne dande (se) Pummy aur Simmy  [ko mara]   
Second part:
Eu            Gd           Tb         Dy           Ho  
Europe   Gaya [to]  TB (aur) Dyarrea Ho gaya
Third part :

Er                                           Tm        Yb        Lu
Ere[pronunce as aaray ]       Tomato  yellow  [ or ] alu [yellow] ?
 
5f series: From thorium [z=90] to lawrencium [z=103] . The eleemnts are callee Actinides.

Th                Pa           U        Np          Pu       Am     Cm     Bk      Fm      Md  No  Lr
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