Question

How many molecules and atoms are present in $5O_2$?

• A. 5, 2
• B. 5, 10
• C. 10, 5
• D. 2, 5

Answer 1

The correct option is B

5, 10

In nature, oxygen exists as a diatomic molecule and hence is represented as $O_2$. Since the number written on the left side of the chemical formula depicts the number of molecules, in the given question there are five molecules. And as one molecule has two atoms of oxygen and here we have 5 molecules, therefore, there are 10 atoms of oxygen.