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

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.

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Yess (B) is correct 14,14

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Yes it is right B

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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

The lanthanides series include elements 58 to 71 which fill their 4f sublevel progressively. The actinides are elements 89 to 103 and fill their 5f sublevel progressively.The lanthanides are f-block elements which contain seven f-orbitals . The maximum electrons can be filled in f-orbitals are 14. Hence, lanthanides have a total 14 elements.The actinide series always includes the 14 elements with atomic numbers 90 through 103. The other members are (in order of increasing atomic number) thorium, protactinium, uranium, neptunium, plutonium, americium, curium, berkelium , californium, einsteinium , fermium, mendelevium, nobelium, and lawrencium.

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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