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The main reason for lanthanoid contraction is    
  • a)
    from left to right in the periodic table, size decreases    
  • b)
    low energy difference between nd and (n - 1)f orbitals    
  • c)
    poor shielding effect exhibited by f-orbital electrons    
  • d)
    low ionisation energy of f-block elements
Correct answer is option 'B'. Can you explain this answer?
Most Upvoted Answer
The main reason for lanthanoid contraction is a)from left to right in ...
Lanthanoid contraction is due to low energy difference between nd and n-1 f orbitals which is due to poor shielding effect exhibited by f orbital elements
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The main reason for lanthanoid contraction is a)from left to right in ...
Lanthanide contraction is the gradual decrease in the atomic and ionic size of lanthanoids with an increase in atomic number.
Causes of lanthanide contraction
  • With an increase in the atomic number, the positive charge on nucleus increases by one unit and one more electron enters same 4f subshell. 
  • The electrons in 4f subshell imperfectly shield each other. Shielding in a 4f subshell is lesser than in d subshell.
  • With the increase in nuclear charge, the valence shell is pulled slightly towards the nucleus. This causes lanthanide contraction.
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The main reason for lanthanoid contraction is a)from left to right in the periodic table, size decreases b)low energy difference between nd and (n - 1)f orbitals c)poor shielding effect exhibited by f-orbital electrons d)low ionisation energy of f-block elementsCorrect answer is option 'B'. Can you explain this answer?
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The main reason for lanthanoid contraction is a)from left to right in the periodic table, size decreases b)low energy difference between nd and (n - 1)f orbitals c)poor shielding effect exhibited by f-orbital electrons d)low ionisation energy of f-block elementsCorrect answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about The main reason for lanthanoid contraction is a)from left to right in the periodic table, size decreases b)low energy difference between nd and (n - 1)f orbitals c)poor shielding effect exhibited by f-orbital electrons d)low ionisation energy of f-block elementsCorrect answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The main reason for lanthanoid contraction is a)from left to right in the periodic table, size decreases b)low energy difference between nd and (n - 1)f orbitals c)poor shielding effect exhibited by f-orbital electrons d)low ionisation energy of f-block elementsCorrect answer is option 'B'. Can you explain this answer?.
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