8.Elements of Group 1 and Group 2
Qno.1. Explain the following A. Hydrogen shows similarity with alkali metals as well as halogens.[2 Marks] Ans:- i. Electronic configuration of hydrogen is 1s¹ which is similar to the outer electronic configuration of alkali metals of group 1 i.e., ns¹. ii. However, 1s¹ also resembles the outer electronic configuration of group 17 elements i.e., ns²np⁵. iii. By adding one electron to H, it will attain electronic configuration of the inert gas He which is 1s² and by adding one electron to ns²np⁵ we get ns²np⁶ which is the outer electronic configuration of the remaining inert gases. iv. Therefore, some chemical properties of hydrogen are similar to those of alkali metals while some resemble halogens. Hence, hydrogen shows similarity with alkali metals as well as halogens. B. Standard reduction potential of alkali metals have high negative values. [2 Marks ] Ans:- i. The general outer electronic configuration of alkali metals is ns¹. ii. They readily lose one valence shel...