Osmosis was discovered by J.A. Nollet in 1748. He experimented with water, wine, and a membrane from a pig's bladder. Instead of the wine being filtered as it passed downwards through the membrane into the water, the water flowed upwards into the wine. This was totally mind boggling and has eluded solution for more than 250 years. We present the complete solution for osmosis. It includes an improved molecular model for solids, liquids, and vapor pressure. This allows a completely new view of Osmosis, diffusion, and molecular behavior of substances. Its applications include chemistry, biology, medicine, physics, diffusion and more. It explains how a single molecule passes through a membrane. It provides the key to: Designing a medicine for diseased cells. Understanding the collection of maple syrup Producing low cost pure water Understanding anatomy and much more "