Because Oxygen is the most abundant element in the universe, i will answer your question with 1kg of O2 (molecule).
1 mole = 32gm
1 gm =1/32 mole
1kg = 1000/32 mole
One mole of any compound is equal to 6.022 x (1023 atoms).
Thus, 1 kg O2 = (1000/32)*(6.022x (10)23) atoms
Roughly, 1.881 x (1025 molecules
Each molecule contains 16 electrons
Also, 3.096 x (1026 electrons.
We are grateful.