Question

III answer the following.

11. Explain Electron affinity?

(or)

Explain atomic radius?

IV answer the following

12. (i)Write the features of Periods
( or)

(ii) Write the features of groups?​

Answer 1

Answer:

attraction force for incoming electron for making uni negative ion is known as electron affinity...

Answer 2

Explanation:

Atomic radius is the distance between electron and outermost shell of atom

groups are vertical rows.elements in same group have same chemical properties