Question

What is the diagonal relationship? Give one example.

Answer 1

• A diagonal relationship is said to exist between certain pairs of diagonally adjacent elements in the second and third periods of the periodic table.
  
• Diagonal relationships occur because of the directions in the trends of various properties as you move across or down the periodic table. Many of the chemical properties of an element are related to the size of the atom.
  
• These pairs (lithium (Li) and magnesium (Mg), beryllium (Be) and aluminum (Al), boron (B) and silicon (Si) etc.) exhibit similar properties; for example, boron and silicon are both semiconductors, forming halides that are hydrolyzed in water and have acidic oxides.