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Question

Lanthanide contraction occurs because

Solution

Correct option is

f-orbital electron are poor shielders of nuclear charge

The size of lanthanides are smaller than expected. This is associated with the filling up of 4f orbitals which must be filled before the 5d orbitals. The electrons in f-orbitals are not effective in screening other electrons from the nuclear charge.

SIMILAR QUESTIONS

Q1

On adding excess of NH3 solution CuSO4 solution, the dark blue colour is due to

Q2

Which statement is not correct?

Q3

Yellow mercury (II) oxide is obtained when

Q4

Which of the following method can’t be used to prepare anhydrous zinc chloride?

Q5

Which lanthanoid compound is used as a most powerful liquid lasers after dissolving it in selenium oxychloride?

Q6

Which one of the following acts as an oxidizing agent?

Q7

Across the lanthanide series, the basicity of lanthanide hydroxides

Q8

The +3 ion of which one of the following has half-filled 4f subshell?

Q9

Actinides

Q10

Which of the following ion is diamagnetic?