Materials are transferred between individual cells and their internal environment through the cell membrane by diffusion, osmosis, and active transport. During diffusion and osmosis, molecules move from a higher concentration to a lower concentration. Osmosis: Osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution. Diffusion: Diffusion is the movement of particles from an area of higher concentration to lower concentration. This would be the diffusion.
... in neutralization reactions, for example:
NaOH + HCl = NaCl + H₂O
2KOH + H₂SO₄ = K₂SO₄ + 2H₂O
90 elements occur naturally on earth.