271.

Assertion : La(OH)₃ is more basic than Lu(OH)₃

Reason : Size of Lu3⁺ increases and shows more covalent character.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false

Lanthanum the first element of lanthanide series has :

• only unfilled 3d orbitals

• unfilled 3d and 4d orbitals

• unfilled 4d and 4forbitals

• unfilled 4f and 5d orbitals

Assertion : F^- ion is a weak ligand and forms outer orbital complex.

Reason : F^- ion cannot force the electrons of d_{${\mathrm{z}}^2$} and d${\mathrm{x}}^2-{\mathrm{y}}^2$ orbitals of the inner shell to occupy d_xy, d_yz and d_zx orbitals of the same shell.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Which of the following has more unpaired d-electrons ?

• Zn

• Fe²⁺

• Ni³⁺

• Cu⁺

How many structural isomers are possible for C₄H₉Cl ?

• 2

• 4

• 8

• 10

What are constituents of 'Mischmetal'?

• La, Fe

• La, Ce

• Fe, Ce

• Ce, Cu

Fungicides are organic compounds of :

• mercury

• fluorine

• lead

• chlorine

In the periodic table actinides occupy :

• III B group in 7th row

• III B group in 6th row

• III B group in 5th row

• None of the above

Which of the following is diamagnetic ?

• CuCl₂

• NiCl₂

• FeCl₃

• Cu₂Cl₂

Why Sc (Z = 21) is not considered as transition element ?

• Properties of Sc are similar to alkali metals

• 3d - orbitals are empty in its stable compound

• Stable oxidation number of Sc is +2

• Atomic volume of Sc is very large