Why a Chest Tube is Placed. A chest tube is placed for a variety of reasons. One reason, as you mentioned, is to help the lung re-inflate when someone has a collapsed lung, also known as a pneumothorax. In that circumstance, a chest tube is inserted along the side of the ribs to allow the lung to reinflate.
A. Osmosis is the passive movement of water from an area high in water concentration, across a semi-permeable membrane, to an area low in water concentration.
In osmosis, molecules also travel from higher concentration to a lower concentration. However, osmosis specifically refers to the movement of WATER molecules. Both of these types of transport are examples of passive transport, which requires no energy. Osmosis is for solids only, while diffusion is for both gases and liquids. In diffusion, molecules travel from a higher concentration to a lower concentration. When you put a drop of ink in a glass of water, the spreading of the ink in the water is called diffusion.