Osmosis :: Papers

Osmosis Introduction Osmosis is the passage of water from a region of high water concentration through a semi-permeable membrane to a region of low water concentration. The aim of the investigation is to find the variables that affect the rate of osmosis and how they affect the rate of reaction. The variables that affect the rate of reaction of osmosis are, Â · The surface area of the object, Â · The concentration of the solution, Â · Temperature of the experiment Surface area If the surface area of the object is larger then more molecules can pass through the semi-permeable membrane. This will ultimately increase the rate of reaction. [IMAGE] [IMAGE] [IMAGE][IMAGE] Small surface area Large surface area Concentration If the concentration of the solution is high then it will contain more molecules and so the rate of reaction will be shorter. [IMAGE] [IMAGE] Low concentration High concentration Temperature of the experiment Generally the higher the temperature, the less time it takes for a reaction. But with living cells there is a point at which the cell will be denatured therefore the rate of reaction will be altered, as the cells are no longer functioning. Hypothesis ========== Osmosis is defined as the movement of water or any other solution's molecules from a region of highly concentrated solution to a region of less concentrated solution. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules such as water through but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found reaches a state of equilibrium, meaning that the molecules are randomly distributed throughout an object, with no area having a higher or lower concentration than any other. To make this investigation fair, the conditions will be as follows: Changed variable Constants