How many elements are placed in lanthanide and actinide series?a)57, 89b)14, 14c)89, 57d)14, 16Correct answer is option 'B'. Can you explain this answer?

Question

Answer

14 elements

The same holds for the actinide series that runs from atomic number 90 through to number 103, again 14 elements. Thus, as you move from thorium (Th) at element number 90, you begin to fill up the 5f sublevel and continue to fill up the 5f sublevel until you finish the actinide series at lawrencium (Lr).

Answer

Lanthanides and Actinides series elements are always having only 14 elements as they are belongs to the 'f - block' elements as per the Modern Periodic table.

Answer

Yess (B) is correct 14,14

Answer

Yes it is right B

Answer

Answer and explanation is wrong.
Answer,15 and 15.
lenthanides is FROM 57 TO 71.
71 MINUS 57 IS 14 .BUT IF YOU COUNT IT ONE BY ONE THEN IT WILL BE 15 NOT 14.
SIMILARLY ACTINIDES WILL BE 15

Answer

Introduction to Lanthanides and Actinides
The lanthanide and actinide series are two important groups of elements in the periodic table, known for their unique properties and placement.
Lanthanide Series
- The lanthanide series consists of 14 elements.
- These elements range from Lanthanum (La, atomic number 57) to Lutetium (Lu, atomic number 71).
- They are known for their f-block configuration, specifically filling the 4f orbitals.
Actinide Series
- The actinide series also comprises 14 elements.
- This series spans from Actinium (Ac, atomic number 89) to Lawrencium (Lr, atomic number 103).
- The actinides fill the 5f orbitals and include many radioactive elements.
Summary of Options
- Option A (57, 89): Incorrect, as it refers only to the starting atomic numbers without counting the total elements.
- Option B (14, 14): Correct, indicating both the lanthanide and actinide series have 14 elements each.
- Option C (89, 57): Incorrect, similar reasoning as option A but in reverse.
- Option D (14, 16): Incorrect, as while 14 is correct for lanthanides, there are only 14 actinides not 16.
Conclusion
The correct answer is option B (14, 14), as both the lanthanide and actinide series consist of 14 elements each. Understanding these series is crucial for grasping the behavior of f-block elements in chemistry.

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