Osmosis Lab Report

Introduction

The reason of this experiment was to identify the properties and effects of osmosis. Osmosis can be defined as the diffusion of water through a selectively permeable membrane. (Miller/Levine) Osmosis occurs when there is an area of higher and lower concentration. Osmosis is a type of diffusion. Diffusion is when molecules move from an area of higher concentration to an area of higher concentration. The three types of concentrations are hypotonic, hypertonic, and isotonic. When in comparison to another solution, a hypertonic solution has a lower concentration, a hypertonic solution has a higher concentration, and an isotonic is when the two solutions have an equal concentration. The experiment tested the relationship between the concentration of an egg and solutions of different concentrations. The hypothesis is that an egg placed in distilled water will gain mass while an egg placed in syrup would lose mass.

Methods

To perform the experiment gloves and safety goggles were obtained. Two decalcified eggs were also obtained from the teacher. Using an electronic scale, the initial mass was measured and recorded of each egg. One egg was then placed in a beaker of distilled water while the other was placed in a beaker of syrup. After a time lapse of ten minutes, each egg was taken out and dabbed to remove excess liquids. After excess liquids had been removed, they were placed on the scale one at a time. The mass was then recorded in a data table. These steps were repeated in ten minute intervals four more times, each time recording the mass in the data table. After all measurements were collected, the percent of mass change was calculated using the formula listed below:

100(Mass after Immersion-Initial Mass)

Initial mass

Results

After the fifty minutes soaking in the solution, the egg placed in water gained mass (Table 1) while the egg placed in syrup lost mass after fifty minutes (Table 2). The percent of mass change was calculated and put onto a graph (Graph 1)

Discussion

The hypothesis that the egg in water would gain mass was proved correct by this experiment. When the egg was placed in the water, the egg was hypertonic and the water was hypotonic. During the fifty minutes water diffused through the egg to higher concentration, the egg. As the water went into the egg it gained mass. If the egg was left in the water for a longer period of time, it would have continued to gain mass until the concentrations were equal, or isotonic.

The hypothesis also stated that the egg in syrup would lose mass. This was also correct. When the egg was in the syrup, the syrup was hypertonic making the egg hypotonic. To equal out the concentration, the water inside of the egg