Question

1. 2. 3 question should be answered​

Answer 1

1.Group 2 A elements called alkaline earth metals as their oxidies were known earlier than the metals ,their oxidies are alkaline and exist in the earth crust

2. lithium is smallest in size among alkali metals .hence Li+ ion can polarize water molecules more easily than other alkali metals.hence lithium salts such as trihydrated lithium chloride are commonly hydrated as the size of ion increases,their polarizing power decreases.

3.in ko2 oxidation state of each oxygen is -1/2

let oxidation state be x

x+2(-1/2)=0

x=+1 is the answer

hope this is useful