d and f BLOCK ELEMENTS

Which of the following is NOT mentioned as an alloying metal added during steel production?

• Cr
• Mn
• Ni
• Cu

For what purpose is TiO mentioned in the text?

• Catalyst
• Semiconductor
• Pigment industry
• High-temperature superconductor

What is a key difference noted between actinoids and lanthanoids regarding chemical reactivity with acids?

• Actinoids are unaffected by all acids.
• Actinoids react with HCl, while lanthanoids react differently with HNO3.
• Lanthanoids are unaffected by acids.
• Actinoids react violently with water only.

Which element is mentioned as being required by the battery industry?

• Fe
• Cu
• Zn
• Ti

Which of the following best describes the general trend in properties for early actinoids?

• Erratic and unpredictable changes
• Large jumps in properties
• Close similarities and gradual variation
• Identical properties to lanthanoids