Question

plz brainly users helps me plz don't post irrelevant answers for points. ........​

Answer 1

Answer:

a

Explanation:

To find the mass of one atom of a element, you need it's molar mass. The molar mass of Oxygen is 16, which can be found in the periodic table.

1 mole of atoms = 6.023*10^23 atoms.

Now, you just divide the molar mass with 6.023*10^23

So, the answer is a.