Respuesta :
Answer: (C) .There are four molecules of sodium sulfite.
Explanation:
[tex]4Na_2SO_4[/tex] means that there are four molecules of sodium sulfite.
Molecule is defined as a group of atoms bonded together. They are smallest unit of the substance which participates in a chemical reaction.
Atom is defined as smallest unit of matter which composed of electrons , protons and neutrons.