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Dconcentrations of solutions determine the mass of a potato Sample Essay


The manner to acquire the full consequences of this lab was through the procedure of osmosis. Osmosis is the motion of H2O across a membrane into a more concentrated solution to make an equilibrium. When sing cells osmosis has three different footings that are used to depict their concentration. The first of these words is isosmotic. Cells in an isosmotic solution show that the H2O has no net motion and the sum of H2O that goes in is the same that goes out. Isotonic comes from the root iso. which means equal. This makes sense because the definition of isotonic is: same concentration. The 2nd out of three words is hypotonic. Cells in a hypotonic solution make the H2O move into the cell to distribute out the cells solutes to finally make an equillibrium. Hypotonic comes from the root word sodium thiosulphate. which means low/below. The existent definition for hypotonic is: less concentrated. Hypertonic is the last out of the three words. A cell in a hypertonic solution makes the H2O leave the cell to seek to distribute out the solutes outside to finally make an equillibrium. Hypertonic comes from the root word hyper. which means more/high. The definition of hypertonic is: more concentrated.

A works cell in two out of three of these conditions can be important to a workss wellness. In an isosmotic solution. a works cell has no net motion of H2O. A word for what occurs is flaccid. When solution is isosmotic the vacuole is non full and that is truly bad because a works needs its foods and a full vacuole makes it stand tall ( turgar force per unit area ) . In a hypertonic solution. the vacuoles lose H2O ; the cytol psychiatrists and chloroplast are seen in the centre of the cell. A word that describes this is plasmolysis. This is bad for a works cell because the abjuration of the cell membrane causes it to rupture/tear.

In this experiment we tested murphies and put them through some solutions that have different concentrations to see what would go on. Would it shrivel or would it swell? Those were the two chief inquiries that were asked in this lab.


Based on anterior cognition I made an educated conjecture on the result of the consequences. For my hypothesis I said that for the molar concentration degree of 0 and. 2 the murphy nucleus was traveling to swell. doing the status the nucleuss were in hypotonic. When the molar concentration turned into. 4 I said that the nucleus would remain the same and hence be isosmotic. When the nucleus was placed in the. 6. . 8. and 1 molar concentration solutions I thought that the nucleuss were traveling to shrink doing the conditions hypertonic. The concluding behind these premises is based on the definition of molar concentration. Molarity is the step how concentrated something is. The concluding why I think its starts to swell at foremost but so shrivel is because the less concentrated a solution is causes it to hold more H2O to be available in its milieus. So the more concentrated the solution is will do there to be less H2O in their surrounding so there wont be every bit much to take in so it will shrivel. At. 4 molar concentration I thought the milieus would be isosmotic merely because it was merely approximately in the center and there wasn’t excessively much or excessively small concentration.


Once the right stuffs were gathered for the experiment procedure the set-up procedure was initiated. First the 5 trial tubings were labeled with their corresponding concentrations of solution. The concentrations consisted of 0m. . 2m. . 4m. . 6m. . 8m. and 1m. The 6 cut up pieces of murphy were weighed individually on a graduated table to roll up their mass. The murphy pieces were all placed into the trial tubing they were assigned after roll uping the informations so there would be no mix-ups. A pipette pump is used to carefully force out the concentrated solutions into their designated trial tubing. The solution was squirted until it covered the murphy wholly. This was repeated with every solution into their own-labeled flasks. After that procedure was finished a piece of parafilm was placed on each of the trial tubing and firmly fastened. The dependent variable in the experiment was the per centum alteration in mass and the independent variable was the solution. This is a quantitative experiment because it was mensurating the per centum alteration in the mass of the murphies.



The chart below shows the % alteration in mass after being in their concentrated solutions:

Following Page ( didn’t tantrum )

Concentration ( M ) 0m. 2m. 4m. 6m. 8m1m

Initial Mass ( g ) 3. 6g3. 8g3. 9g3. 1g3. 0g3. 0g

Concluding Mass ( g ) 4. 1g3. 9g3. 4g2. 2g2. 0g1. 9g

% Change in Mass14. 9 % 1. 8 % -12. 1 % -28. 6 % -33. 3 % -36. 9 %


The Graphs below show the per centum alterations in mass for both the category norms and our group’s norms:


In decision when the molar concentration degree was at 0 and at. 2 the murphies had gained mass so hence they were placed in a hypotonic environments. When the molar concentration degree was. 4 and above the murphies loss mass so hence they were placed in hypertonic environments. So the different in concentrations does alter the mass of the murphies because they determine the osmosis environments.


The hypothesis for this experiment was that at 0m and at. 2m the murphy nucleus was traveling to swell doing the milieus it was in hypotonic. For. 4m it was stated that the murphy nucleus would remain the same. doing the milieus it was in isosmotic. For that last three solutions. . 6m. . 8m. and 1m. it was thought that they would shrivel. so that would intend that that the environment that they were placed in was hypertonic. Although these consequences made sense merely the existent consequences can give the right reply. After roll uping the information it was revealed that the premises made for the 0m and. 2m solutions were right.

The information had showed that to 0m solution had a 14. 9 % alteration in mass and the. 2m solution had a 1. 8 % alteration in mass. These per centums showed that the murphies had gained mass. For the. 4m solution. the hypothesis made was wrong. The information showed that there was a -12. 1 % alteration in mass. This proved that in this solution the murphy nucleus had lost mass and it was assumed that the mass would remain the same. For the. 6m. . 8m. and 1m solutions the hypothesis was proven right. The consequences showed that for the. 6m solution at that place was a -28. 6 % alteration in mass. for the. 8m solution at that place was a -33. 3 % alteration in mass. and for the 1m solution at that place was a -36. 9 % alteration in mass. This all proved that the murphies had lost mass in these solutions.

Some countries of mistake were largely during the procedure of weighing the murphies and seting the right solution into their designated trial tubings. For illustration there was some point in which it was unsure if one of the solutions was already put into a trial tubing or non. If the solution was put into two different trial tubings that could hold lead to a false positive or false negative consequence depending on what the molar concentration degree of the solution was. Besides in the weighing procedure of the concluding mass the murphies were taken out of the trial tubings were they were soaked in the solution. The entree solution left on the murphy can be transferred to the graduated table and give the mass a more positive consequence doing it a false positive. This could hold been avoided by pass overing off the entree H2O of the graduated table.

Even though the murphy pieces were cut into regular hexahedrons every bit best as humanly possible the murphy pieces did stop up being different sizes. Although this seemed like a set back it wasn’t because the alteration in the murphy nucleuss was measured by the difference in mass by mensurating the murphy before and after. Surface country won’t affect osmosis. merely if the point used was thicker it could forestall more H2O from acquiring in. but otherwise surface country can merely rush up or down osmosis.

If alterations could be made to this experiment there are some things that were considered. For illustration the murphy pieces could hold been cut with more forbearance so that they were every bit equal to each other as possible. Besides the whole experiment could be doubled by holding twice every bit many murphies to set in 2 trial tubings of each solution. This would guarantee that the consequences had fewer errors. Besides there can be other fluctuations of this experiment by holding other start points that aren’t needfully murphies. These alterations can do a large difference in the survey of osmosis.

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