F Block Elements Mock Tests

14 questions available

F Block Elements Mock Test 1

Questions: 14

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CUET Chemistry

Lanthanoid contraction is caused by the incomplete shielding of one another by electrons in which subshell?

A 5d subshell

B 6p subshell

C 4f subshell

D 6s subshell

CUET Chemistry

The actinoid contraction is more pronounced than the lanthanoid contraction because:

A 5f electrons shield the nuclear charge even more poorly than 4f electrons

B Actinoids have more valence electrons

C Actinoids are all radioactive

D The nuclear charge is lower in actinoids

CUET Chemistry

Which lanthanoid exhibits the +4 oxidation state in addition to the characteristic +3 oxidation state?

A Praseodymium

B Cerium

C Europium

D Ytterbium

CUET Chemistry

What is the most effective method for separating lanthanoids from each other?

A Crystallisation

B Solvent extraction

C Ion exchange chromatography

D Distillation

CUET Chemistry

Which of the following lanthanoid ions is diamagnetic? (Atomic numbers: Ce = 58, Pr = 59, Nd = 60, Lu = 71)

A Ce⁴⁺

B Pr³⁺

C Nd³⁺

D Sm³⁺

CUET Chemistry

Which of the following statements is correct about lanthanoid contraction?

A It is due to poor shielding of 4f electrons leading to smaller atomic sizes across the series

B It is due to strong shielding of 4f electrons leading to larger atomic sizes across the series

C It causes an increase in atomic size from La to Lu

D It occurs in actinoids but not in lanthanoids

CUET Chemistry

All actinoids are radioactive. Which actinoid has the longest-lived isotope and what is its half-life?

A Uranium-238 (4.5 × 10⁹ years)

B Thorium-232 (1.4 × 10¹⁰ years)

C Plutonium-239 (2.4 × 10⁴ years)

D Neptunium-237 (2.1 × 10⁶ years)

CUET Chemistry

The lanthanoid contraction is responsible for which of the following observations?

A Lanthanoids are highly reactive non-metals

B The atomic radii of Zr (40) and Hf (72) are nearly identical

C Lanthanoids have low ionisation enthalpies

D The basicity of lanthanoid hydroxides increases across the series

F Block Elements Mock Tests

F Block Elements Mock Test 1

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