GKFix MCQ Question

What is the role of the 4f orbitals in determining the properties of 5d series elements?

• A. They provide excellent shielding for 5d electrons
• B. Their poor shielding causes Lanthanoid contraction, affecting 5d element sizes
• C. They determine the number of valence electrons in 5d elements
• D. They have no effect on 5d element properties