d and f BLOCK ELEMENTS

What does the text suggest about the elements known in 1800 compared to today?

• There are fewer elements known today
• There are significantly more elements known today
• The number has remained roughly the same
• Only 31 elements exist in total

What is the connection between the reactivity of elements and their classification, according to the text?

• Reactivity determines the block classification
• Classification makes all elements equally reactive
• Classification helps compare reactivity and link it to natural occurrence
• Reactivity is random and unrelated to classification

Which of the following blocks is NOT one of the classifications mentioned for elements based on electronic configuration?

• s block
• p block
• f block
• g block

What is one of the goals of examining periodic trends in element properties, as stated in the text?

• To synthesize new elements
• To determine the age of elements
• To examine periodic trends in physical and chemical properties
• To calculate atomic weights precisely

Based on the text, what is a key factor that makes studying all elements and their compounds challenging without classification?

• The high cost of chemicals
• The lack of laboratory space
• The sheer number of elements and compounds
• The instability of elements