d and f BLOCK ELEMENTS

Which lanthanoid element is known to commonly exhibit a +4 oxidation state?

• Neodymium
• Promethium
• Cerium
• Dysprosium

Which lanthanoid element is known to commonly exhibit a +2 oxidation state?

• Cerium
• Europium
• Samarium
• Gadolinium

What is the typical range of oxidation states exhibited by actinoid elements?

• +1 to +3
• +2 to +7
• +3 to +6
• +4 to +7

Compared to lanthanoids, why is the chemistry of actinoids described as more complicated?

• They have more electrons
• They are synthetic
• Due to the occurrence of a wide range of oxidation states and their radioactivity
• They are found deeper in the Earth's crust

What is the primary reason lanthanoids resemble each other so closely?

• Identical number of valence electrons
• Similar atomic masses
• Filling of inner 4f orbitals which do not significantly participate in bonding
• They all have the same number of electron shells