d and f BLOCK ELEMENTS

Based on the information, what is the effect of lanthanoid contraction on the separation of second and third series elements?

• Makes separation easy
• Has no effect on separation
• Makes separation difficult
• Makes separation impossible

Why is the shielding of one 4f electron by another considered imperfect?

• 4f electrons are held too tightly
• 4f orbitals are diffuse and have complex shapes leading to poor overlap
• 4f electrons repel each other strongly
• There are too many 4f electrons

According to Table 4.2, what is the approximate ionic radius of Ni2+?

• 60 pm
• 70 pm
• 73 pm
• 75 pm

What is the electronic configuration of a Co2+ ion?

• [Ar] 3d5
• [Ar] 3d6
• [Ar] 3d7
• [Ar] 3d8

Based on Table 4.2, which element has the lowest enthalpy of atomisation?

• Manganese (Mn)
• Iron (Fe)
• Zinc (Zn)
• Vanadium (V)