Question

15 Who am I? (Each clue represents a single Element)
a) I am essential to human beings for their healthy teeth and bone
b) I am 78% in the air. I am responsible for growth of plants
c)I am used to kill bacteria in drinking water ​

Answer 1

Answer:

a) Calcium or Ca

b) nitrogen gas or N2

c) Chlorine or Cl2

Answer 2

Answer:

a) Calcium

b) nitrogen

c) Chlorine

Explanation:

We drink milk because it contains calcium to strengthen our bones and teeth

Plants need oxygen to grow

we add chlorine to water in swimming pools to kill bacteria