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.
passive transport. the movement of molecules of a particular substance from regions of high concentration to regions of low concentration of that substance, i.e. down a CONCENTRATION GRADIENT. The rate of diffusion in gases is much greater than in liquids, due to differences in their molecular structure.