Name any two elements of group one and write their electronic configuration

Name any two elements of group one and write their electronic configuration. What similarity do you observe in their electronic configurations? Write the formula of oxide of any of the aforesaid elements.

(i) Two elements of group one are Na (sodium) and potassium (K).
(ii) Electronic configuration: Na (11) : 2, 8, 1; K (19) : 2, 8, 8, 1.
(iii) Similarity: Both elements have 1 valence electron. So, they are in same group.
(iv) Oxides: (a) Na20 ; Sodium oxide ; (b) KaO : Potassium oxide.