Molarity Of Sucrose Lab Report

Aim: To find the concentration of a potato cell cytoplasm compared to sucrose and salt. I mainly was looking to see how concentration of salt/sucrose affects the mass of the potato cores.

As the Concentration of the Sucrose Solution decreases, the more the potato’s mass increases. This is due to the solution being hypertonic. So, as the solute concentration gets lower, the potato’s water concentration will get higher, therefore more water particles from the solution will absorbed by the potato. Some changed very little in mass because the concentrations of the H2O molecules in the potato and outside the potato were equal. This equality in concentration is called Isotonic.

We kept the volume at a constant 0.50 L and first set up the moles to 1.00 moles. The molarity of Co(NO3)2 was 2.00 mol/L. When we decreased the number of solute moles to 0.50 moles, the molarity of the solution was 1.00 mol/L. The quantitative data was collected and we concluded that the relationship between the number of solute moles and the molarity of the solution was direct for the reason that whenever the the moles increased, the molarity increased. However, when the moles decreased the molarity decreases as well. We then combined the two relationships to conclude that the derived unit for molarity is the number of moles/volume of the solution. We believe our claim is right because it was not opinion based. Our theory is proven by facts and that is the simple reason. To conclude, our claim is that the relationships consist of the following: number of moles of the solute is directly proportionate to the molarity of the solution; the volume of the solution is inversely proportionate to the molarity of the solution; and that the derived units for the molarity are number of moles of the solute per the volume of the

In the experiment I performed it was proven that, the moles of a solute, the volume of the solvent, and the molarity of an aqueous solution share a mathematical relationship. Solutions, solutes and molarity are all terms that are crucial to chemistry. A solution is defined as a liquid mixture in which the solute is distributed into the major component, and a solute is defined as the minor component within a solution. The molarity of a solution is the number of moles of solute per liter of solution and it is used to express the concentration of a solution. Both the solute amount and the solution volume can be determined in experiments to aid finding the solution concentration or molarity of a substance that they are included in. I state confidently

Figure 1: Percentage change in potato tuber mass vs. sucrose concentration. The percent change in mass decreased as the sucrose concentration increased. Relative osmotic concentration was measured as the percent change in mass of sucrose concentration over one hour.

When the final mass was measured the excess water in the potato cube might have not been completely removed, thus it adds to the final mass of the potato cubes. This acts as a major error because it gives an inaccurate representation of the actual percentage change in mass of the potato cubes, also while measuring the mass of each cube of potato; the value fluctuated and was not consistent.

Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is

Van’t Hoff’s Law suggests that the osmotic potential of a cell is proportional to the concentration of solute particles in a solution. The purpose of this experiment was to determine if there are any differences between the osmolalities, the no-weight-changes of osmolalities, and the water potentials of potato cores in different solutions of different solutes. The percent weight change of the potato cores was calculated through a “change in weight” method. The potato core’s weight was measured before and after they were put into different concentrations of a solute for 1.5 hours. In our experiment, there were no significant differences from the osmotic potentials of our results and the osmotic potentials of other scientists work. Ending with chi square values of 2.17 and 2.71, and p values of 0.256 and 0.337, concluding that there is no difference in water potentials of potato cores in different solutions of different solutes at varying concentrations.

The percentage change in mass was 6.7%. This result is reflected in the graph at point (0, 6.7). Thus, the concentration is hypotonic because the potato piece gained water and mass. In the 0.2m salt solution the potato lost mass.

Effect of Sucrose Solution on Osmosis Aim: The aim of the experiment is to show how varying the concentration of sucrose solution affects osmosis by changing different molar solutions of sucrose and water and how it affects the potato. Introduction: In this investigation I will be exploring the effect of varying concentration of sucrose sugar solution on the amount of activity between the solution and the potatoes. Osmosis is the movement of water molecules across a partially permeable membrane from a high water concentration to a low water concentration.

If the C.melo is put in the lowest sucrose concentration, then it will cause an increase in mass because the water molecules pass from an area of high water potential, although the water itself, to an are of low water potential in the C.melo. As a result of this, the C.melo in the concentrations of sucrose with a lower water potential will reduce the initial mass as the water potential is higher inside of the C.melo, than in the sugar concentrations. The “net movement” (in the direction of increased concentrations) of the water molecules is into the cell, and the cell will increase in mass.

In conclusion when the molarity level was at 0 and at .2 the potatoes had gained mass so therefore they were placed in a hypotonic environments. When the molarity level was .4 and above the potatoes loss mass so therefore they were placed in hypertonic environments. So the different in concentrations does change the mass of the potatoes because they determine the osmosis environments.

This would happen by using similar sizes and lengths of potato cylinders and applying the into different concentrations of sucrose (0,10%,30%, 50%, 70%) in foam cups then measuring the change in mass of the potato cylinders afterwards. Maintaining all variables unchanged such as pH, same size, covered solutions, and a constant temperature. The time taken for all potato cylinders will be 24 hours.

In 1909 S.P.L. Sorensen published a paper in Biochem Z in which he discussed the effect of H1+ ions on the activity of enzymes. In the paper he invented the term pH to describe this effect and defined it as the -log[H1+ ]. In 1924 Sorensen realized that the pH of a solution is a function of the &quot;activity&quot; of the H1+ ion not the concentration and published a second paper on the subject. A better definition would be pH=-log[aH1+ ], where aH1+ denotes the activity of the H1+ ion. The activity of an ion is a function of many variables of which concentration is one. It is unfortunate that chemistry texts use a definition for pH that has been obsolete for over 50 years.

As we can see in Figure’s 1.2 and 1.3, when there was no sucrose solution, the potato increased in weight. This is due to the fact that the sucrose solution was hypertonic in comparison to the potato slice. Through osmosis, the solution moved along the concentration gradient and into the potato slice making it hypotonic. When there were higher concentrations of sucrose solution, the potato decreased in weight. This is due to the fact that the potato was hypertonic in comparison to the potato. Through osmosis, sucrose from the potato moved along the concentration gradient out and into