Answer:
- Li and K have same chemical properties
- O and Se have same chemical properties
- He and Ar have same chemical properties
Step-by-step explanation:
According to modern periodic table, the elements present into same group group have same chemical properties due to same valence shells electrons.
Li and K have same chemical properties:
Both these elements are present in same group i.e group 1 known as alkali atoms. Almost all alkali metals have same chemical properties.
O and Se have same chemical properties
Both these elements are present in same group VI A. The elements present in same group have same chemical properties.
He and Ar have same chemical properties
Both these elements are present in same group VIII A called it noble gases. The elements present in same group have same chemical properties both are inert.