Question

Short note on diagonal relationship

Answer 1

In a periodic table, an element of a group in the second period is similar in properties with the second element of next group. This type of relation is called Diagonal relationship
Second period    Li      Be        B      C

Third period          Na  Mg      Al        Si
Li-Mg
Be-Al
B and Si
Reasons :
Similar atomic size or ionic size
similar electronegativity
Similar polarising power.
Diagonally related elements have same chemical properties.