Question

In this

B and c part how to identify it is metal and non metal

Answer 1

Answer:

if the valency of element is below 4 then it is metal

if the valency of element is greater than 4 than it is non metal

if the valency of element is 4 then it is metalloid

Answer 2

For grade X all u need to know is elements belonging to group less than 14 r usuallymetals and more than 14 are non metals or metalloids